HEMMERT CATHERINE (FR)
DERAEVE CÉLINE (FR)
CUVILLIER OLIVIER (FR)
MADDELEIN MARIE-LISE (FR)
MALAVAUD BERNARD (FR)
QIN XUE (FR)
WANG XING (FR)
UNIV TOULOUSE III PAUL SABATIER (FR)
CENTRE HOSPITALIER UNIV DE TOULOUSE (FR)
CLAIMS 1. An iridium(III) complex of formula (I) in which Z- represents a halide anion, a nitrate anion (-NO3-) or a non-coordinating anion, -R1- represents a covalent link or a spacer segment, the radical R2 represents a targeting entity or ferrocene, the radicals R3 and R4, identical or different, represent a hydrogen atom, a halogen atom, an alkyl group optionally substituted, an aryl group optionally substituted, an alkylaryl group optionally substituted, an arylalkyl group optionally substituted, an ether group (-OR), an amine group (-NRR’), a borane group (-BRR’), a thioether group (-SR), and a phosphine group (-PRR’); the radicals R5, R6, R7 and R8, identical or different, represent a hydrogen atom, a halogen atom, a hydroxyl group or an ether group (-OR), a cyano group (- CN), a nitro group (-NO2), a carboxylic group or a carboxylic acid ester group (- C(=O)OR), an alkyl group optionally substituted, an aryl group optionally substituted, an alkylaryl group optionally substituted, an arylalkyl group optionally substituted, an aldehyde group or a ketone group (-C(=O)R), an amine group (-NRR’), a cyanate group (-OC≡N), an isocyanate group (-N=C=O), a carboxamide group (-C(=O)NRR’), a boronic acid group (-B(OR)2), a sulfhydryl group or a thioether group (-SR), an iminothiol group (-C(NR)SR’) and a trimethylsilylacetylene group (-CCSiMe3); N the ligands are either of formula (II) or of formula (III) R19 R18 in which (X1, X2) represents either (N, C ) or (C , N), the radicals R9 to R24, identical or different, represent a hydrogen atom, a halogen atom, a cyano group (-CN), a nitro group (-NO2), a carboxylic group or a carboxylic acid ester group (-COOR), an alkyl group optionally substituted, an aryl group optionally substituted, an alkylaryl group optionally substituted or an arylalkyl group optionally substituted; the radicals R9 and R10, the radicals R10 and R11, the radicals R11 and R12, the radicals R12 and R13, the radicals R13 and R14, the radicals R14 and R15, the radicals R15 and R16, the radicals R17 and R18, the radicals R18 and R19, the radicals R19 and R20, the radicals R21 and R22, the radicals R22 and R23 and the radicals R23 and R24 may form with the carbons to which they are attached a conjugated system of delocalized electrons, R and R’, identical or different, representing a hydrogen atom or an alkyl group optionally substituted. 2. The iridium(III) complex according to claim 1, wherein said non- coordinating anion is selected from the group consisting of tetrafluoroborate (BF4-), hexafluorophosphate (PF6-), benzenesulfonate (CH5SO3-), bis(trifluoromethanesulfonyl)imide ((N[SO2(CF3)]2)-), methanesulfonate (mesylate, CH3SO3-), perchlorate (ClO4-), tetrachloroaluminate (AlCl4-), tetrakis[3,5- bis(trifluoromethyl)phenyl]borate (B[3,5-(CF3)2C6H3]4-), tetrakis (hexafluoroisopropyl)aluminate (Al[OC(CF3)3]4-), tetrakis(pentafluorophenyl) borate (B[C6F5]4-), p-toluene sulfonate (tosylate, CH3C6H4SO2-) and trifluoromethanesulfonate (triflate, CF3SO3-). 3. The iridium(III) complex according to claim 1 or 2, wherein said spacer segment is selected from the group consisting of an alkylene chain optionally substituted, an alkenylene chain optionally substituted, an alkynylene chain optionally substituted and an arylene chain optionally substituted. 4. The iridium(III) complex according to any one of claims 1 to 3, wherein said targeting entity is selected from the group consisting in PSMA (for “Prostate Specific Membrane Antigen”) inhibitor such as any antibody specifically binding PSMA or the molecule Lys-urea-Glu; the cyclic tripeptide Arg-Gly-Asp (RGD); Herceptin; Trastuzumab; antibody specifically binding to the nectin 4 antigen; biotin and FTS (for “Farnesyl Thiosalicylic Acid”). 5. The iridium(III) complex according to any one of claims 1 to 4, wherein said radicals R3 and R4 are any one of the combinations defined in the below Table 1 with R, R’, R’’, R’’’ and R’’’’, identical or different, representing a hydrogen atom or an alkyl group optionally substituted. Combination R3 R4 1 H H 2 Me Me 3 CRR’R” H, SR”’, NR”’R””, OR”’ 4 OR H, OR’ 5 NR’R” H, NR”’R”” 6 SR H, SR’ 7 PRR’ H, PR”R”’ 8 F H 9 BRR’ H 10 H, SR”’, NR”’R””, OR”’ CRR’R” 11 H, OR’, OR 12 H, NR”’R”” NR’R” 13 H, SR’ SR 14 H, PR”R”’ PRR’ 15 H F 16 H BRR’ Table 1 6. The iridium(III) complex according to any one of claims 1 to 5, wherein said radicals R5, R6, R7, and R8 are any one of the combinations defined in the below Table 2 with R and R’, identical or different, representing a hydrogen atom or an alkyl group optionally substituted. Combination R5 R6 R7 R8 20 H H H H 21 H H H Me, CN, OMe, CF3, C(O)R, CH2OH, CHF2, NHR, pyridine, COOR, NR2, F, B(OR)2 22 H H Me, CN, H OMe, CF3, C(O)R, CH2OR, CHF2, NHR, pyridine, COOR, NR2, F, CH2NHR, B(OR)2, CH2CN, NCO, NO2, CCSiMe3, SMe, C(NR)SR’ H Me, Et, CN, H H OMe, CF3, C(O)R, CH2OR, CRF2, NHR, pyridine, COOR, NR2, F, CH2NHR, B(OR)2, CH2CN, NCO, NO2, CCSiMe3, SMe, C(NR)SR’, C(O)NHR Me, CN, OMe, H H H CF3, C(O)R, CH2OR, CHF2, NHR, pyridine, COOR, NR2, F, CH2NHR, B(OR)2, CH2CN, NCO, NO2, CCSiMe3, SMe, C(NR)SR’ Me, NH2, H F H C(O)H NH2, NO2 H Me H F, H COOR H Me, CN H NO2 H C(O)R H F, CF3, Ph H H H NH2, COOR NH2 H H Me, F, COOR Me H H C(O)H F H H OMe, B(OR)2, OMe COOR, C(O)R H H Me C(O)R NH2 NH2, Me, CF3 H H CF3 F, COOR H H COOR NHR H H 38 CN B(OR)2 H H 39 F C(O)R H H 40 NO2 Me H H 41 NO2 H H OMe 42 COOR H H CF3 43 NHR H H CH2OR, COOR 44 H Me, COOR NHR H 45 H Me NO2 H Table 2 7. The iridium(III) complex according to any one of claims 1 to 6, wherein said iridium(III) complex is of any one of the following formulae (IV), (V), (VI) and H 8. The iridium(III) complex according to any one of claims 1 to 7, wherein said ligands C^N is selected from the group consisting of 2-phenylpyridine (ppy (a)), 2-p-tolylpyridine (4-Me-ppy (b)), methyl 4-(pyridin-2-yl)benzoate (4-COOMe- ppy (c)), methyl 3-(pyridin-2-yl)benzoate (3-COOMe-ppy (d)), methyl 6- phenylnicotinate (p-3-COOMe-ppy (e)), 6-phenylnicotinic acid (p-3-COOH-ppy (f)), 2-phenylquinoline (pq (g)), 1-phenylisoquinoline (piq (h)), 7,8-benzoquinoline (bzq (i)), 2-(2-pyridyl)benzothiophene (thpy (j)), 2-phenylbenzothiazole (pbt (k)), and 2-(2,4-difluorophenyl)pyridine (2,4-F-ppy (l)). 9. The iridium(III) complex according to any one of claims 1 to 8, for use as a medicament . 10. A pharmaceutical composition comprising, as active ingredient, an iridium(III) complex according to any one of claims 1 to 8 and a pharmaceutically acceptable vehicle. 11. The iridium(III) complex according to any one of claims 1 to 8 or the pharmaceutical composition according to claim 10, for use in the treatment and/or prevention of cancer. 12. The iridium(III) complex or the pharmaceutical composition, for use according to claim 11, wherein said cancer is selected from the group consisting of melanoma, colorectal cancer, colon cancer, Kaposi's sarcoma, glioblastoma, ovarian cancer, breast cancer, liver cancer, pancreatic cancer, lung cancer, bladder cancer, prostate cancer, or neuroendocrine tumors. 13. The iridium(III) complex or the pharmaceutical composition, for use according to claim 11 or 12, wherein - the iridium(III) complex is of formula (IV) as defined in claim 8 in which the C^N ligands are either 2-phenylquinolines (pq (g)) or 2-phenylbenzothiazoles (pbt (k)) and the cancer to be treated and/or prevented is bladder cancer, or - the iridium(III) complex is of formula (V) as defined in claim 8 in which the C^N ligands are selected in the group consisting of 1-phenylisoquinolines (piq (h)), 2-(2-pyridyl)benzothiophenes (thpy (j)) and 2-phenylbenzothiazoles (pbt (k)) and the cancer to be treated and/or prevented is bladder cancer, or - the iridium(III) complex is of formula (VI) as defined in claim 8 in which the C^N ligands are either 1-phenylisoquinolines (piq (h)) or 2- phenylbenzothiazoles (pbt (k)) and the cancer to be treated and/or prevented is prostate cancer, or - the iridium(III) complex is of formula (VII) as defined in claim 8 in which the C^N ligands are either 1-phenylisoquinolines (piq (h)) or 2-(2- pyridyl)benzothiophenes (thpy (j)) and the cancer to be treated and/or prevented is bladder cancer or prostate cancer. 14. The iridium(III) complex according to any one of claims 1 to 8 or the pharmaceutical composition according to claim 10, for use in diagnosis and, in particular, in photodynamic diagnosis. |
Scheme 2 i. Synthesis of (S)-2-[(imidazole-1-carbonyl)amino]pentanedioic acid di- tert-butyl ester (6) To a suspension of L-di-tert-butyl glutamate hydrochloride (1.0 g, 3.40 mmol) in DCM (10 mL) cooled to 0°C were added TEA (1.5 mL) and DMAP (17 mg). After the mixture was stirred for 5 min, CDI (0.6 g, 3.74 mmol) was added and the mixture was stirred overnight with warming to room temperature. The mixture was diluted with DCM (20 mL) and washed with saturated sodium bicarbonate (60 mL), water (2 × 100 mL), and brine (100 mL). The organic layer was dried over sodium sulfate and concentrated to afford the crude product as semisolid, which slowly solidified upon standing. The crude material was triturated with hexane/ethyl acetate to afford a white solid which was filtered, washed with hexane (100 mL), and dried under vacuum to afford the desired product (1.06 g, 2.99 mmol, 88%). 1 H NMR (300 MHz, CDCl3): δ 8.19 (s, 1H), 7.55 (d, J = 6.7 Hz, 1H), 7.43 (dd, J = 1.5 Hz, 1H), 7.10 (dd, J = 1.6, 0.9 Hz, 1H), 4.46 (m, 1H), 2.44 (m, 2H), 2.16 (m, 2H), 1.45 (s, 9H), 1.50 (s, 9H). ii. Synthesis of (S)-2-[3(S)-(5-benzyloxycarbonylamino)-1-tert-butyl ester] (7) To a solution of (6) (1.0 g, 2.82 mmol) in DCE (10 mL) at 0°C were added MeOTf (0.47 g, 2.85 mmol) and TEA (0.57 g, 5.65 mmol). After the solution was stirred for 30 min, Cbz-Lys-Ot-Bu (1.06 g, 2.82 mmol) was added in one portion and allowed to stir for 1 h at 40°C. The mixture was concentrated to dryness and purified by column chromatography (SiO 2 ) with CH 2 Cl 2 /MeOH (50:1) as the eluent to afford the desired product as a white solid (1.37 g, 78%). 1 H NMR (300 MHz, CDCl 3 ): δ 7.28 (m, 5H), 5.26-5.09 (m, 3H), 5.08 (d, J = 7.4 Hz, 2H), 4.26 (m, 2H), 3.09 (m, 2H), 2.22 (m, 2H), 2.08-1.45 (m, 8H), 1.39-1.34 (m, 27H). iii. Synthesis of 2-[3-(5-amino-1-tert-butoxycarbonylpentyl)ureido] pentanedioic acid di-tert-butyl ester (8) To a solution of (7) (630 mg, 1.00 mmol) in ethanol (20 mL) was added ammonium formate (630 mg, 10 eqv.) followed by 10% Pd-C, and the suspension was stirred overnight until the hydrogenolysis was complete. The reaction was followed by TLC. The mixture was filtered through a pad of celite and concentrated to dryness to afford the desired product (479 mg, 0.98 mmol, 98%) as a waxy solid. 1 H NMR (400 MHz, CDCl 3 ): δ 7.06-5.03 (bm, 4H), 4.33 (m, 2H), 3.02 (m, 2H), 2.33 (m, 2H), 2.16-1.52 (m, 8H), 1.50-1.41 (m, 27H). iv. Synthesis of (9) (3) (1.0 g, 3.36 mmol), NHS (0.38 g, 3.36 mmol) and DCC (0.9 g, 4.36 mmol) in DMF (10 mL) were stirred at r.t.. After one night, the solution was filtered and cold diethyl ether (100 mL) was added to the filtrate, affording precipitation. The crude was filtered out and washed with DCM (3 × 10 mL) and cold diethyl ether (3 × 10 mL) to afford the NHS-activated intermediate as a white solid. To a solution of this intermediate, (8) (1.5 g, 3.08 mmol) and TEA (2 mL, 14.64 mmol) in DCM (10 mL) were added and the resulting mixture was stirred at r.t.. After one night, the solution was concentrated to dryness and purified by column chromatography (Al2O3) with CH2Cl2/MeOH (50:1) as the eluent to afford the desired product as a pale-yellow oil (1.0 g, 43%). Anal. Calcd. For C35H55BrN6O8: C, 54.75; H, 7.22; N, 10.95. Found: C, 54.53; H, 7.16; N, 10.81. 1 H NMR (300 MHz, CDCl3): δ 10.80 (s, 1H), 8.48 (ddd, J = 4.8, 1.9, 0.8 Hz, 1H), 8.44- 8.38 (m, 1H), 8.35 (dd, J = 1.9 Hz, 1H), 8.31 (ddd, J = 8.3, 0.9 Hz, 1H), 8.02 (ddd, J = 8.3, 7.5, 1.9 Hz, 1H), 7.97-7.94 (m, 1H), 7.41 (ddd, J = 7.5, 4.8, 0.8 Hz, 1H), 6.68 (d, J = 7.5 Hz, 1H), 6.49 (d, J = 8.2 Hz, 1H), 4.76 (t, J = 6.5 Hz, 2H), 4.31 (td, J = 8.4, 5.0 Hz, 1H), 4.00 (td, J = 7.5, 4.6 Hz, 1H), 3.28 (dd, J = 6.2 Hz, 2H), 3.21-2.99 (m, 2H), 2.36-2.28 (m, 2H), 2.09-1.93 (m, 2H), 1.80 (dtd, J = 13.7, 8.8, 7.0 Hz, 2H), 1.54 (ddd, J = 14.6, 8.2, 4.5 Hz, 2H), 1.38 (s, 9H), 1.37 (s, 9H), 1.35 (s, 9H), 1.20-1.14 (m, 2H). 13 C NMR (101 MHz, CDCl 3 ): δ 173.3 (1C), 172.5 (1C), 172.4 (1C), 169.0 (1C), 158.1 (1C), 149.0 (1C), 146.0 (1C), 140.9 (1C), 134.7 (1C), 125.2 (1C), 124.2 (1C), 118.9 (1C), 114.7 (1C), 81.3 (1C), 80.7 (1C), 80.3 (1C), 53.5 (1C), 52.9 (1C), 47.8 (1C), 37.8 (1C), 35.5 (1C), 31.9 (1C), 30.4 (1C), 28.2 (1C), 28.1 (3C), 28.0 (6C), 27.9 (1C), 21.4 (1C). (ES + ): calcd. for C 35 H 55 N 6 O 8 687.4081; found 687.4066 [M-Br-] + . v. Synthesis of (III) To a solution of (9) (0.83 g, 1.078 mmol) in DCM (10 mL) cooled to 0°C was added TFA (1 mL). After the mixture was stirred for 5 min, the solution was warmed to room temperature and stirred for 3 h. The solution was concentrated to dryness and washed with DCM (3 × 10 mL) and dried under vacuum to afford the desired product as a pale-yellow oil (0.63 g, 98%). Anal. Calcd. For C 23 H 31 BrN 6 O 8 : C, 46.08; H, 5.21; N, 14.02. Found: C, 46.14; H, 5.03; N, 14.74. 1 H NMR (400 MHz, MeOD): δ 9.89 (s, 1H), 8,65 (dd, J = 4.9, 1.8 Hz, 1H), 8.41 (dd, J = 1.9 Hz, 1H), 8.15 (td, J = 7.9, 1.8 Hz, 1H), 7.94 (d, J = 8.2 Hz, 1H), 7.87 (dd, J = 1.9 Hz, 1H), 7.61 (dd, J = 7.9, 4.9 Hz, 1H), 4.66 (t, J = 6.3 Hz, 2H), 4.33 (dd, J = 8.7, 5.0 Hz, 1H), 4.21 (dd, J = 8.6, 4.8 Hz, 1H), 3.23-3.13 (m, 2H), 2.93 (t, J = 6.3 Hz, 2H), 2.54-2.32 (m, 2H), 2.24-2.08 (m, 1H), 1.94-1.85 (m, 1H), 1.84-1.75 (m, 1H), 1.64- 1.54 (m, 1H), 1.54-1.42 (m, 2H), 1.42-1.30 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 175.1 (1C), 175.0 (1C), 174.6 (1C), 169.9 (1C), 158.7 (1C), 149.4 (1C), 146.5 (1C), 140.3 (1C), 135.1 (1C), 125.1 (1C), 123.5 (1C), 119.2 (1C), 113.6 (1C), 52.5 (1C), 52.2 (1C), 46.3 (1C), 38.7 (1C), 34.9 (1C), 31.8 (1C), 29.8 (1C), 28.3 (1C), 27.4 (1C), 22.5 (1C). HRMS (ES + ): calcd. for C23H31N6O8519.2203; found 519.2216 [M-Br-] + . B.4. Synthesis of ferrocene vectorized proligand (IV) The proligand containing a ferrocene (Fc) moiety 1-(3- ((ferrocenylcarbonyl)amino)propyl)-3-(pyridin-2-yl)-1H-imida zol-3-ium bromide (IV), was obtained by reaction of ferrocenoyl chloride (obtained from (10) [5] and oxalyl chloride) and (2) in the presence of triethylamine (Scheme 3). Scheme 3 i. Synthesis of ferrocenecarboxylic acid (10) A mixture of ferrocene carboxaldehyde (1.0 g, 4.67 mmol) and KOH (4.0 g, 71 mmol) in MeOH (4 mL) was stirred at 60°C overnight. After cooling down to room temperature, DCM (20 mL) was poured into the crude and the product was extracted with deionized water (3 × 20 mL). The water layer was concentrated to remove MeOH, acidified by HCl (1 M) to pH = 5 in an ice bath, resulting in precipitation. After filtration and drying under vacuum, the desired product was obtained as a yellow solid (0.48 g, 47%). 1 H NMR (400 MHz, CDCl3): δ 4.88 (s, 2H), 4.49 (s, 2H), 4.28 (s, 5H). ii. Synthesis of 1-(3-((Ferrocenylcarbonyl)amino)propyl)-3-(pyridin-2-yl)- 1H-imidazol-3-ium bromide (IV) To a solution of (10) (1.0 g, 4.3 mmol) in DCM (8 mL) stirred at 0°C for 5 min, was added slowly (COCl)2 (0.74 mL, 8.6 mmoL) in DCM (2 mL) at 0°C. The resulting mixture was stirred overnight at r.t. and dried under vacuum to afford the intermediate ferrocenoyl chloride (FcCOCl), which was then reacted with (2) (1.5 g, 4 mmol), and TEA (2.2 mL, 16 mmol) in DCM (10 mL) at r.t.. After one night, the solution was concentrated to dryness and purified by column chromatography on Al 2 O 3 with CH 2 Cl 2 /MeOH (50:1) as the eluent, yielding a brown waxy solid (1.30 g, 75%). Anal. Calcd. For C 22 H 23 BrFeN 4 O: C, 53.36; H, 4.68; N, 11.31. Found: C, 53.11; H, 4.74; N, 11.28. 1H NMR (400 MHz, CDCl 3 ): δ 12.09 (s, 1H), 8.53-8.49 (m, 3H), 8.24 (dd, J = 1.9 Hz, 1H), 8.13-7.91 (m, 1H), 7.60 (dd, J = 1.8 Hz, 1H), 7.47 (dd, J = 7.7, 5.1 Hz, 1H), 5.09 (dd, J = 2.0 Hz, 2H), 4.74-4.53 (m, 2H), 4.26-4.18 (m, 7H), 3.57-3.48 (m, 2H), 2.50-2.28 (m, 2H). 13C NMR (101 MHz, CDCl 3 ): δ 171.7 (1C), 148.9 (1C), 145.9 (1C), 140.6 (1C), 136.5 (1C), 125.1 (1C), 122.3 (1C), 118.8 (1C), 114.9 (1C), 75.7 (1C), 70.4 (2C), 69.7 (5C), 68.7 (2C), 48.3 (1C), 35.7 (1C), 29.5 (1C). HRMS (ES + ): calcd. for C 22 H 23 N 4 OFe 415.1221; found 415.1223 [M-Br-] + . I.3. Synthesis of vectorized iridium(III) complexes. Commercially available C^N-proligands including 2-phenylpyridine (ppy (a)), 2-p-tolylpyridine (4-Me-ppy (b)), methyl 4-(pyridin-2-yl)benzoate (4-COOMe- ppy (c)), methyl 3-(pyridin-2-yl)benzoate (3-COOMe-ppy (d)), methyl 6- phenylnicotinate (p-3-COOMe-ppy (e)), 6-phenylnicotinic acid (p-3-COOH-ppy (f)), 2-phenylquinoline (pq (g)), 1-phenylisoquinoline (piq (h)), 7,8-benzoquinoline (bzq (i)), 2-(2-pyridyl)benzothiophene (thpy (j)), 2-phenylbenzothiazole (pbt (k)), and 2-(2,4-difluorophenyl)pyridine (2,4-F-ppy (l)) (Schemes 4 and 5) were incorporated into the Ir(III) center of the vectorized iridium complexes, in order to modulate the lipophilic/hydrophilic balance and the excitation wavelengths of the corresponding iridium complexes. The dichloro-bridged dimers [IrCl(C^N)2]2 [6,7] were prepared according to the literature (Schemes 4 and 5). The vectorized iridium(III) complexes (I-a) to (I-l), (II-a-e) to (II-g-l), (III-a- b), (III-d-e) to (III-g-l) and (IV-a) to (IV-l) were prepared by reacting the suitable iridium dimer [IrCl(C^N)2]2 with the suitable proligand (I), (II), (III) or (IV) in the presence of the mild base Ag2O, followed by an anion exchange with an excess of KPF6 or NH4PF6 (Schemes 4 and 5). Complex (I-f) was a byproduct of (I-e). COOCH 3 Scheme 5 A. Synthesis of complexes (Ia)-(Ie), (Ig)-(Il) and (IIa) to (II-l). The iridium(III) dimers [(C^N)2IrCl]2were prepared according to literature procedures [6,7]. A.1. General protocol for the synthesis of complexes (Ia)-(Ie), (Ig)-(Il) and (IIa) to (II-l) A mixture of one equivalent of [(C^N) 2 IrCl] 2 , two equivalents of (I) or (II) and two equivalents of Ag 2 O in MeOH or DMF or MeCN was heated at 85°C overnight. After cooling down, the mixture was filtered through a pad of celite and evaporated to dryness. The resulting residue was purified by column chromatography on aluminium oxide with a mixture of CH 2 Cl 2 and MeOH as eluent to give a solid. The solid was dissolved in 5 mL MeOH, an aqueous solution of KPF6 (200 mg in 10 mL deionized water) was slowly added under stirring, affording precipitation of the complex. The resulting solid was filtered and dried under vacuum. A.2. Complex (I-a) From [(ppy)2IrCl]2 (105 mg, 0.1 mmol), (I) (100 mg, 0.2 mmol) and Ag2O (44 mg, 0.2 mmol) in 5 mL of MeOH. Eluent CH2Cl2 and MeOH (10:1). Yellow solid (119 mg, 56% yield). Anal. Calcd. For C43H44F6IrN8O2PS: C, 48.08; H, 4.13; N, 10.43. Found: C,48.27; H; 4.31; N, 10.31. 1 H NMR (600 MHz, DMSO-d6): δ 8.61 (s, 1H), 8.41 (d, J = 8.4 Hz, 1H), 8.28-8.20 (m, 2H), 8.21 (m, 1H), 7.95 (m, 3H), 7.90 (d, J = 8.0 Hz, 2H), 7.75 (s, 1H), 7.71 (s, 1H), 7.65 (d, J = 6.0 Hz, 1H), 7.61 (d, J = 5.6 Hz, 1H), 7.44 (dd, J = 6.1 Hz, 1H), 7.16 (m, 2H), 7.03 (dd, J = 7.1, 4.4 Hz, 1H), 6.94 (m, 2H), 6.83 (dd, J = 7.8 Hz, 1H), 6.42 (s, 1H), 6.38 (s, 1H), 6.28 (d, J = 7.6 Hz, 1H), 6.12 (d, J = 7.4 Hz, 1H), 4.31 (t, J = 6.3 Hz, 1H), 4.12 (t, J = 5.7 Hz, 1H), 3.35-3.46 (m, 2H), 3.08 (s, 1H), 2.85-2.75 (m, 1H), 2.58 (m, 3H), 2.02 (t, J =12.2 Hz, 2H), 1.45- 1.60 (s, 2H), 1.47 (m, 2H), 1.29 (m, 2H), 1.17-1.30 (m, 2H). 13 C NMR (151 MHz, DMSO-d 6 ): δ 178.1 (1C), 172.5 (1C), 168.3 (1C), 167.0 (1C), 164.1 (1C), 163.2 (1C), 153.7 (1C), 153.6 (1C), 149.6 (1C), 149.4 (1C), 149.4 (1C), 145.0 (1C), 143.4 (1C), 142.2 (1C), 139.0 (1C), 138.3 (1C), 130.9 (2C), 130.8 (1C), 130.1 (1C), 125.4 (2C), 125.0 (1C), 124.8 (2C), 124.0 (1C), 123.3 (1C), 121.8 (1C), 120.7 (1C), 120.4 (1C), 118.9 (1C), 113.4 (1C), 61.5 (1C), 59.7 (1C), 55.9 (1C), 47.6 (1C), 40.5 (1C), 35.8 (1C), 35.5 (1C), 32.0 (1C), 28.7 (1C), 28.5 (1C), 25.7 (1C). HRMS (ES + ): calcd. for C 43 H 44 IrN 8 O 2 S 929.2937; found 929.2933 [M-PF 6 -] + . A.3. Complex (I-b) From [(4-Me-ppy) 2 IrCl] 2 (199 mg, 0.18 mmol), (I) (180 mg, 0.35 mmol) and Ag 2 O (81 mg, 0.35 mmol) in 5 mL of MeOH. Eluent CH 2 Cl 2 and MeOH (10:1). Yellow solid (106 mg, 27% yield). Anal. Calcd. For C 45 H 48 F 6 IrN 8 O 2 PS: C, 49.04; H, 4.39; N, 10.17. Found: C, 48.85; H; 4.56; N, 10.27. 1 H NMR (400 MHz, MeOD): δ 8.27 (d, J = 2.2 Hz, 1H), 8.18-8.05 (m, 3H), 8.01 (d, J = 8.1 Hz, 1H), 7.94 (d, J = 5.8 Hz, 1H), 7.88-7.77 (m, 3H), 7.70 (dd, J = 9.7, 8.0 Hz, 2H), 7.62 (d, J = 5.9 Hz, 1H), 7.50 (d, J = 2.2 Hz, 1H), 7.28 (ddd, J = 7.1, 5.6, 1.5 Hz, 1H), 7.04 (m, 2H), 6.85 (dd, J = 8.2, 1.4 Hz, 1H), 6.80 (dd, J = 8.1, 1.6 Hz, 1H), 6.25 (s, 1H), 6.06 (s, 1H), 4.53-4.48 (m, 1H), 4.33-4.28 (m, 1H), 3.68-3.48 (m, 2H), 3.24-3.16 (m, 1H), 2.92 (dd, J = 12.8 Hz, 5.0 Hz, 1H), 2.73-2.63 (m, 3H), 2.18 (t, J = 7.2 Hz, 2H), 2.07 (s, 6H), 1.80-1.70 (m, 1H), 1.70-1.49 (m, 4H), 1.47-1.37 (m, 2H), 1.37-1.37 (m, 1H). 13 C NMR (101 MHz, MeOD): δ 179.5 (1C), 174.5 (1C), 169.0 (1C), 167.4 (1C), 164.7 (1C), 163.7 (1C), 153.5 (1C), 152.7 (1C), 149.6 (1C), 149.1 (1C), 148.6 (1C), 141.9 (1C), 141.3 (1C), 140.4 (1C), 140.4 (1C), 140.0 (1C), 137.9 (1C), 137.2 (1C), 131.4 (1C), 131.4 (1C), 124.6 (1C), 124.6 (1C), 123.8 (1C), 123.7 (2C), 123.2 (1C), 122.3 (1C), 122.2 (1C), 119.5 (1C), 119.3 (1C), 117.6 (1C), 112.3 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 47.4 (1C), 39.7 (1C), 35.8 (1C), 35.2 (1C), 31.5 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C), 20.5 (2C). HRMS (ES + ): calcd. for C 45 H 48 IrN 8 O 2 S 957.3290; found 957.3246 [M-PF 6 - ] + . A.4. Complex (I-c) From [(4-COOMe-ppy) 2 IrCl] 2 (156.5 mg, 0.12 mmol), (I) (121 mg, 0.24 mmol) and Ag 2 O (55.6 mg, 0.24 mmol) in 5 mL of DMF. Eluent CH 2 Cl 2 and MeOH (10:1). Yellow solid (156 mg, 55% yield). Anal. Calcd. For C 47 H 48 F 6 IrN 8 O 6 PS: C, 47.43; H, 4.07; N, 9.41. Found: C, 47.23; H, 4.12; N, 9.38. 1 H NMR (400 MHz, MeOD): δ 8.33 (d, J = 2.2 Hz, 1H), 8.30 (d, J = 8.3 Hz, 1H), 8.26-8.12 (m, 3H), 8.07 (d, J = 5.7 Hz, 1H), 8.04-7.96 (m, 2H), 7.96-7.85 (m, 2H), 7.81-7.74 (m, 2H), 7.64 (dd, J = 8.2, 2.4 Hz, 1H), 7.59 (dd, J = 8.2, 2.1 Hz, 1H), 7.55 (d, J = 2.2 Hz, 1H), 7.33 (ddd, J = 7.1, 5.6, 1.2 Hz, 1H), 7.24 (m, 2H), 7.04 (d, J = 1.7 Hz, 1H), 6.88 (d, J = 1.7 Hz, 1H), 4.64-4.46 (m, 1H), 4.35-4.23 (m, 1H), 3.72 (s, 6H), 3.64-3.49 (m, 2H), 3.21 (m, 1H), 2.93 (ddd, J = 12.7, 5.0, 1.5 Hz, 1H), 2.71 (dd, J = 12.7, 3.3 Hz, 1H), 2.70- 2.54 (m, 2H), 2.16 (t, J = 7.3 Hz, 2H), 1.79-1.52 (m, 5H), 1.52-1.39 (m, 2H), 1.34- 1.20 (m, 1H). 13 C NMR (101 MHz, MeOD): δ 177.9 (1C), 174.5 (1C), 167.3 (2C), 167.1 (1C), 165.9 (1C), 164.6 (1C), 162.3 (1C), 153.5 (1C), 153.4 (1C), 149.7 (1C), 149.4 (1C), 149.3 (1C), 147.8 (1C), 147.7 (1C), 141.7 (1C), 138.6 (1C), 137.9 (1C), 131.3 (2C), 130.7 (1C), 130.3 (1C), 125.2 (1C), 124.5 (1C), 124.4 (1C), 124.3 (2C), 124.1 (1C), 123.9 (1C), 122.7 (1C), 121.2 (1C), 121.0 (1C), 117.9 (1C), 112.7 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 51.0 (2C), 47.4 (1C), 39.7 (1C), 35.7 (1C), 35.2 (1C), 31.4 (1C), 28.3 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C47H48IrN8O6S 1045.3047; found 1045.3037 [M-PF6-] + . A.5. Complex (I-d) From [(3-COOMe-ppy)2IrCl]2 (189 mg, 0.15 mmol), (I) (146 mg, 0.29 mmol) and Ag2O (67.2 mg, 0.29 mmol) in 5 mL of DMF. Eluent CH2Cl2 and MeOH (10:1). Yellow solid (75 mg, 17% yield). Anal. Calcd. For C47H48F6IrN8O6PS: C, 47.43; H, 4.07; N, 9.41. Found: C, 47.25; H, 4.04; N, 9.55. 1 H NMR (400 MHz, MeOD): δ 8.54-8.44 (m, 2H), 8.38-8.30 (m, 2H), 8.24 (d, J = 7.9 Hz, 2H), 8.22-8.14 (m, 1H), 8.07-7.93 (m, 3H), 7.77-7.69 (m, 2H), 7.60-7.52 (m, 2H), 7.52-7.43 (m, 1H), 7.36-7.27 (m, 1H), 7.21 (m, 2H), 6.56 (dd, J = 8.1, 1.9 Hz, 1H), 6.36 (d, J = 7.8 Hz, 1H), 4.51 (dd, J = 7.9, 4.9 Hz, 1H), 4.31 (dd, J = 7.9, 4.5 Hz, 1H), 3.87-3.82 (m, 6H), 3.65-3.46 (m, 2H), 3.21 (m, 1H), 2.92 (dd, J = 12.7, 5.0 Hz, 1H), 2.78-2.57 (m, 3H), 2.15 (t, J = 7.2 Hz, 2H), 1.79-1.54 (m, 4H), 1.54-1.25 (m, 4H). 13 C NMR (101 MHz, MeOD): δ 177.8 (1C), 174.5 (1C), 171.4 (1C), 167.8 (2C), 167.5 (1C), 166.1 (1C), 164.7 (1C), 158.0 (1C), 153.4 (1C), 153.3 (1C), 149.5 (1C), 149.3 (1C), 145.3 (1C), 143.8 (1C), 141.9 (1C), 138.9 (1C), 138.2 (1C), 131.0 (2C), 130.7 (1C), 130.1 (1C), 125.3 (1C), 125.2 (1C), 125.1 (1C), 124.9 (1C), 124.2 (1C), 124.1 (1C), 123.9 (1C), 123.7 (1C), 120.5 (1C), 120.3 (1C), 118.0 (1C), 112.8 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 51.1 (2C), 47.9 (1C), 39.7 (1C), 35.7 (1C), 35.2 (1C), 31.4 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 47 H 48 IrN 8 O 6 S 1045.3047; found 1045.3040 [M-PF 6 -] + . A.6. Complexes (I-e) and (I-f) From [(p-3-COOMe-ppy)2IrCl]2 (215 mg, 0.17 mmol), (I) (169 mg, 0.33 mmol) and Ag 2 O (76.5 mg, 0.33 mmol) in 5 mL of DMF. Eluent CH 2 Cl 2 and MeOH (10:1) and CH2Cl2 and MeOH (5:1). Yellow solids ((I-e): 133 mg, 17% yield, ((I-f): 128 mg, 17%). (I-e): Anal. Calcd. For C47H48F6IrN8O6PS: C, 47.43; H, 4.07; N, 9.41. Found: C, 47.34; H; 4.18; N, 9.51. 1 H NMR (400 MHz, MeOD): δ 8.47 (m, 1H), 8.42-8.34 (m, 3H), 8.29-8.19 (m, 4H), 8.15 (m, 1H), 7.99-7.90 (m, 2H), 7.84 (d, J = 5.3, 1H), 7.61 (d, J = 2.2 Hz, 1H), 7.40 (ddd, J = 7.1, 5.6, 1.5 Hz, 1H), 7.10 (dd, J = 7.5, 1.3 Hz, 1H), 7.04 (m, 2H), 6.95 (dd, J = 7.3, 1.2 Hz, 1H), 6.46 (d, J = 7.8 Hz, 1H), 6.28 (dd, J = 7.5, 1.3 Hz, 1H), 4.51 (m, 1H), 4.31 (m, 1H), 3.89 (s, 3H), 3.82 (s, 3H), 3.69-3.45 (m, 2H), 3.20 (m, 1H), 2.92 (d, J =12.7 Hz, 1H), 2.82-2.66 (m, 3H), 2.17 (t, J = 4.3 Hz, 2H), 1.78-1.68 (m, 1H), 1.68-1.52 (m, 4H), 1.52-1.36 (m, 3H). 13 C NMR (101 MHz, MeOD): δ 178.2 (1C), 174.6 (1C), 172.5 (1C), 171.0 (1C), 164.7 (1C), 164.6 (1C), 163.5 (2C), 154.1 (1C), 153.6 (1C), 150.8 (1C), 150.0 (1C), 143.4 (1C), 142.0 (1C), 141.8 (1C), 138.7 (1C), 138.6 (1C), 137.8 (1C), 131.7 (1C), 131.3 (1C), 131.0 (2C), 126.4 (2C), 125.9 (1C), 125.0 (1C), 124.2 (1C), 124.0 (1C), 123.3 (1C), 121.8 (1C), 119.6 (1C), 119.3 (1C), 118.2 (1C), 112.8 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 52.0 (1C), 51.8 (1C), 47.5 (1C), 39.7 (1C), 35.8 (1C), 35.2 (1C), 31.4 (1C), 28.3 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 47 H 48 IrN 8 O 6 S 1045.3047; found 1045.3060 [M-PF 6 -] + . (I-f): Anal. Calcd. For C 45 H 44 F 6 IrN 8 O 6 PS: C, 46.51; H, 3.82; N, 9.64. Found: C, 46.33; H; 3.90; N, 9.55. 1 H NMR (400 MHz, MeOD): δ 8.55 (d, J = 1.7 Hz, 1H), 8.37-8.29 (m, 2H), 8.25 (d, J = 2.3 Hz, 1H), 8.22 (m, 1H), 8.19-8.06 (m, 4H), 7.86 (ddd, J = 8.5, 4.4, 2.8 Hz, 2H), 7.79 (m, 1H), 7.42 (d, J = 2.2 Hz, 1H), 7.27 (ddd, J = 7.1, 5.6, 1.4 Hz, 1H), 7.04 (dd, J = 7.5, 1.3 Hz, 1H), 7.00-6.91 (m, 2H), 6.84 (dd, J = 7.4, 1.4 Hz, 1H), 6.42 (dd, J = 7.8, 1.2 Hz, 1H), 6.26 (dd, J = 7.4, 1.3 Hz, 1H), 4.47 (dd, J = 7.9, 4.8 Hz, 1H), 4.28 (ddd, J = 7.8, 4.5, 3.1 Hz, 1H), 3.64-3.41 (m, 2H), 3.17 (m, 1H), 2.89 (ddd, J = 12.8, 9.9, 5.0 Hz, 1H), 2.83-2.62 (m, 3H), 2.17 (t, J = 7.4 Hz, 2H), 1.77-1.50 (m, 6H), 1.40 (m, 2H). 13 C NMR (101 MHz, MeOD): δ 178.9 (1C), 174.6 (1C), 169.8 (1C), 169.1 (1C), 168.9 (1C), 168.4 (1C), 164.7 (1C), 164.1 (1C), 154.6 (1C), 153.7 (1C), 150.3 (1C), 149.7 (1C), 149.5 (1C), 144.1 (1C), 142.6 (1C), 141.1 (1C), 138.5 (1C), 137.7 (1C), 133.3 (1C), 132.5 (1C), 131.1 (2C), 130.5 (1C), 130.0 (1C), 125.1 (2C), 123.6 (2C), 122.7 (1C), 121.2 (1C), 118.8 (1C), 118.4 (1C), 117.7 (1C), 112.6 (1C), 62.0 (1C), 60.2 (1C), 55.6 (1C), 47.5 (1C), 39.6 (1C), 36.0 (1C), 35.3 (1C), 31.3 (1C), 28.3 (1C), 28.0 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C45H44IrN8O6S 1017.2812; found 1017.2709 [M-PF6-] + . A.7. Complex (I-g) From [(pq)2IrCl]2 (178.1 mg, 0.14 mmol), (I) (143 mg, 0.28 mmol) and Ag2O (64.9 mg, 0.28 mmol) in 5 mL of MeOH. Eluent CH2Cl2 and MeOH (20:1). Orange solid (94 mg, 42% yield). Anal. Calcd. For C51H48F6IrN8O2PS: C, 52.17; H, 4.12; N, 9.54. Found: C, 52.27; H; 4.36; N, 9.67. 1 H NMR (400 MHz, MeOD) : δ 8.48 (m, 2H), 8.33-8.29 (m, 2H), 8.18-8.11 (m, 1H), 8.08-8.00 (m, 2H), 7.95-7.89 (m, 2H), 7.85-7.77 (m, 3H), 7.71 (d, J = 8.8 Hz, 1H), 7.52-7.35 (m, 4H), 7.23-7.14 (m, 2H), 7.03 (m, 3H), 6.77 (dd, J = 7.4, 1.2 Hz, 1H), 6.70 (dd, J = 7.0, 1.6 Hz, 1H), 6.63 (dd, J = 7.9, 1.3 Hz, 1H), 6.23 (dd, J = 7.4, 1.3 Hz, 1H), 4.45 (m, 1H), 4.28 (dd, J = 7.9, 3.9 Hz, 1H), 3.67 (m, 1H), 3.47 (ddd, J = 13.2, 10.5, 5.6 Hz, 1H), 3.16 (m, 1H), 2.86 (ddd, J = 15.7, 12.7, 5.0 Hz, 2H), 2.74 (ddd, J = 13.8, 8.1, 6.2 Hz, 1H), 2.65 (d, J = 12.7 Hz, 1H), 2.20 (t, J = 7.2 Hz, 2H), 1.78-1.50 (m, 5H), 1.42 (m, 2H), 1.23 (m, 1H). 13 C NMR (101 MHz, MeOD): δ 179.8 (1C), 174.6 (1C), 171.6 (1C), 170.7 (1C), 164.7 (1C), 164.0 (1C), 152.6 (1C), 149.8 (1C),148.3 (1C), 147.0 (2C), 146.8 (1C), 144.8 (1C), 141.4 (1C), 140.2 (1C), 139.5 (1C), 132.5 (2C), 131.0 (1C), 130.7 (2C), 130.6 (1C), 129.2 (2C), 128.0 (2C), 127.1 (1C), 127.0 (1C), 126.6 (2C), 126.3 (1C), 124.5 (1C), 123.7 (1C), 123.5 (1C), 123.3 (1C), 121.6 (1C), 118.0 (1C), 117.7 (1C), 117.5 (1C), 112.1 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 47.5 (1C), 39.7 (1C), 36.0 (1C), 35.3 (1C), 30.7 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 51 H 48 IrN 8 O 2 S 1029.3250; found 1029.3259 [M-PF 6 -] + . A.8. Complex (I-h) From [(piq) 2 IrCl] 2 (184.5 mg, 0.15 mmol), (I) (114 mg, 0.29 mmol) and Ag 2 O (67.2 mg, 0.29 mmol) in 5 mL of MeOH. Eluent CH 2 Cl 2 and MeOH (20:1). Orange solid (147 mg, 43% yield). Anal. Calcd. For C 51 H 48 F 6 IrN 8 O 2 PS: C, 52.17; H, 4.12; N, 9.54. Found: C, 52.25; H; 4.27; N, 9.69. 1 H NMR (400 MHz, MeOD): δ 9.04 (m, 1H), 8.95 (d, J = 8.2 Hz, 1H), 8.42 (d, J = 8.1 Hz, 1H), 8.36 (d, J = 2.2 Hz, 1H), 8.28 (d, J = 8.0 Hz, 1H), 8.23 (d, J = 8.3 Hz, 1H), 8.14 (ddd, J = 8.4, 7.5, 1.7 Hz, 1H), 8.06-7.99 (m, 2H), 7.91-7.74 (m, 5H), 7.60 (m, 1H), 7.55 (dd, J = 6.5, 1.2 Hz, 1H), 7.53-7.43 (m, 3H), 7.28 (ddd, J = 7.3, 5.7, 1.2 Hz, 1H), 7.12 (m, 2H), 6.94 (dd, J = 7.4, 1.2 Hz, 1H), 6.82 (m, 1H), 6.40 (dd, J = 7.8, 1.5 Hz, 1H), 6.26 (dd, J = 7.5, 1.3 Hz, 1H), 4.47 (m, 1H), 4.25 (ddd, J = 11.1, 7.9, 4.5 Hz, 1H), 3.59-3.48 (m, 1H), 3.46- 3.36 (m, 1H), 3.21-3.02 (m, 1H), 2.87 (ddd, J = 16.6, 12.8, 5.0 Hz, 1H), 2.69 (ddd, J = 16.8, 10.7, 4.9 Hz, 3H), 2.16-2.05 (m, 2H), 1.75-1.42 (m, 5H), 1.35 (m, 3H). 13 C NMR (101 MHz, MeOD): δ 179.9 (1C), 174.5 (1C), 170.1 (1C), 167.8 (1C), 165.6 (1C), 164.6 (1C), 153.5 (1C), 152.5 (1C), 149.4 (1C), 146.0 (1C), 144.7 (1C), 144.4 (1C), 141.4 (1C), 140.8 (1C), 137.0 (1C), 136.6 (1C), 131.7 (1C), 131.4 (1C), 131.3 (1C), 131.2 (1C), 130.7 (1C), 130.4 (2C), 130.0 (1C), 128.7 (2C), 127.4 (1C), 127.2 (1C), 126.9 (1C), 126.3 (3C), 123.8 (2C), 122.4 (1C), 122.1 (1C), 121.2 (1C), 121.0 (1C), 117.8 (1C), 112.5 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 47.5 (1C), 39.6 (1C), 35.8 (1C), 35.2 (1C), 31.4 (1C), 28.5 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 51 H 48 IrN 8 O 2 S 1029.3250; found 1029.3257 [M-PF 6 -] + . A.9. Complex (I-i) From [(bzq) 2 IrCl] 2 (245.3 mg, 0.21 mmol), (I) (216.5 mg, 0.42 mmol) and Ag 2 O (97.3 mg, 0.42 mmol) in 5 mL of MeOH. Eluent CH 2 Cl 2 and MeOH (20:1). Orange solid (189 mg, 40% yield). Anal. Calcd. For C 47 H 44 F 6 IrN 8 O 2 PS: C, 50.31; H, 3.95; N, 9.99. Found: C, 50.33; H, 4.02; N, 9.84. 1 H NMR (400 MHz, MeOD): δ 8.47-8.40 (m, 3H), 8.30 (d, J = 1.95 Hz, 1H), 8.18 (d, J = 8.3 Hz, 1H), 8.11-8.04 (m, 2H), 7.86 (dd, J = 8.8, 2.5 Hz, 2H), 7.78 (dd, J = 8.9, 1.1 Hz, 1H), 7.76-7.70 (m, 2H), 7.51 (m, 2H), 7.48-7.44 (m, 2H), 7.41 (d, J = 7.8 Hz, 1H), 7.18-7.12 (m, 2H), 7.07 (dd, J = 7.6, 1.7 Hz, 1H), 6.38 (d, J = 7.3 Hz, 1H), 6.25 (d, J = 6.91 Hz, 1H), 4.48 (dd, J = 7.4, 4.5 Hz, 1H), 4.28 (dd, J = 7.9, 4.5 Hz, 1H), 3.56-3.31 (m, 2H), 3.22-3.10 (m, 1H), 2.90 (dt, J = 12.8, 5.2 Hz, 1H), 2.72-2.63 (m, 1H), 2.35 (dd, J = 13.9, 6.9 Hz, 1H), 2.23 (dd, J = 13.9, 7.2 Hz, 1H), 2.10 (t, J = 7.0, 2H), 1.77-1.49 (m, 4H), 1.44- 1.31 (m, 2H), 1.30-1.17 (m, 1H), 0.83-0.71 (m, 1H). 13 C NMR (101 MHz, MeOD): δ 178.2 (1C), 174.3 (1C), 164.7 (1C), 160.8 (1C), 158.1 (1C), 156.9 (1C), 153.9 (1C), 152.1 (1C), 150.1 (1C), 148.1 (1C), 145.4 (1C), 141.4 (1C), 141.0 (1C), 140.1 (1C), 137.2 (1C), 136.3 (1C), 134.6 (1C), 134.4 (1C), 129.8 (1C), 129.7 (1C), 129.6 (1C), 129.2 (1C), 128.4 (1C), 127.9 (1C), 127.6 (1C), 127.3 (1C), 123.8 (2C), 123.6 (1C), 123.5 (1C), 122.6 (1C), 121.8 (1C), 120.7 (1C), 119.1 (1C), 117.7 (1C), 112.4 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 47.6 (1C), 39.7 (1C), 35.5 (1C), 35.2 (1C), 31.2 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C47H44IrN8O2S 977.2937; found 977.2927 [M-PF6-] + . A.10. Complex (I-j) From [(thpy)2IrCl]2 (195 mg, 0.15 mmol), (I) (153 mg, 0.30 mmol) and Ag2O (69.5 mg, 0.30 mmol) in 5 mL of MeOH. Eluent CH2Cl2 and MeOH (20:1). Orange solid (164 mg, 46% yield). Anal. Calcd. For C47H44F6IrN8O2PS3: C, 47.59; H, 3.74; N, 9.45. Found: C, 47.39; H, 3.69; N, 9.34. 1 H NMR (400 MHz, MeOD): δ 8.32 (d, J = 2.2 Hz, 1H), 8.18 (d, J = 8.5 Hz, 1H), 8.04 (ddd, J = 8.5, 7.6, 1.7 Hz, 1H), 7.97- 7.84 (m, 3H), 7.82-7.75 (m, 1H), 7.75-7.66 (m, 5H), 7.53 (d, J = 2.2 Hz, 1H), 7.18- 7.06 (m, 3H), 6.98 (m, 2H), 6.89 (m, 1H), 6.81 (dd, J = 8.1, 7.1 Hz, 1H), 6.15 (m, 1H), 5.96 (d, J = 8.2 Hz, 1H), 4.48 (dd, J = 8.0, 4.8 Hz, 1H), 4.28 (ddd, J = 8.0, 4.5, 1.6 Hz, 1H), 3.48 (d, J = 7.2 Hz, 2H), 3.18 (m, 1H), 2.91 (dd, J = 12.7, 4.8 Hz, 1H), 2.69 (dd, J = 12.7, 2.7 Hz, 1H), 2.49-2.31 (m, 2H), 2.11 (t, J = 7.2 Hz, 2H), 1.78-1.48 (m, 4H), 1.37 (m, 4H). 13 C NMR (101 MHz, MeOD): δ 174.4 (1C), 173.6 (1C), 165.4 (1C), 164.6 (1C), 164.5 (1C), 162.3 (1C), 153.7 (1C), 153.4 (1C), 149.8 (2C), 146.5 (1C), 146.2 (1C), 145.5 (1C), 143.6 (1C), 142.6 (1C), 142.0 (1C), 139.6 (1C), 138.7 (1C), 138.6 (1C), 134.2 (1C), 125.7 (1C), 125.3 (1C), 125.0 (2C), 124.3 (1C), 124.2 (1C), 124.0 (1C), 123.8 (1C), 123.0 (1C), 122.7 (1C), 122.0 (1C), 120.4 (1C), 119.8 (1C), 119.4.0 (1C), 118.1 (1C), 112.7 (1C), 62.0 (1C), 60.2 (1C), 55.7 (1C), 47.6 (1C), 39.7 (1C), 35.6 (1C), 35.1 (1C), 31.4 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 47 H 44 IrN 8 O 2 S 3 1041.2379; found 1041.2366 [M-PF 6 -] + . A.11. Complex (I-k) From [(pbt) 2 IrCl] 2 (213.9 mg, 0.17 mmol), (I) (168 mg, 0.33 mmol) and Ag 2 O (76.5 mg, 0.33 mmol) in 5 mL of MeOH. Eluent CH 2 Cl 2 and MeOH (20:1). Yellow solid (142 mg, 36% yield). Anal. Calcd. For C47H44F6IrN8O2PS3: C, 47.59; H, 3.74; N, 9.45. Found: C, 47.66; H, 3.75; N, 9.37. 1 H NMR (400 MHz, MeOD): δ 8.42 (d, J = 2.2 Hz, 1H), 8.22 (d, J = 8.4 Hz, 1H), 8.13 (m, H, 1H), 8.08 (ddd, J = 8.2, 3.2, 1.2 Hz, 1H), 8.01 (dd, J = 8.0, 1.7 Hz, 1H), 7.90-7.82 (m, 3H), 7.68 (d, J = 2.2 Hz, 1H), 7.48-7.34 (m, 3H), 7.30 (ddd, J = 7.2, 5.6, 1.2 Hz, 1H), 7.14 (ddd, J = 8.5, 7.2, 1.2 Hz, 1H), 7.01 (dd, J = 7.5, 1.2 Hz, 1H), 6.95 (dd, J = 7.5, 1.0 Hz, 1H), 6.89 (dd, J = 7.4, 1.3 Hz, 1H), 6.76 (dd, J = 7.5, 1.4 Hz, 1H), 6.44 (ddd, J = 8.9, 7.7, 1.7 Hz, 2H), 6.37 (d, J = 7.9 Hz, 1H), 6.18 (d, J = 8.4 Hz, 1H), 4.46 (dd, J = 8.2, 4.1 Hz, 1H), 4.28 (dd, J = 7.5, 4.4 Hz, 1H), 3.69-3.51 (m, 2H), 3.17 (m, 1H), 2.86 (ddd, J = 12.7, 11.0, 4.9 Hz, 1H), 2.80-2.61 (m, 3H), 2.17 (t, J = 7.2 Hz, 2H), 1.79-1.51 (m, 5H), 1.39 (m, 3H). 13 C NMR (101 MHz, MeOD): δ 183.2 (1C), 180.0 (1C), 175.6 (1C), 174.5 (1C), 164.6 (1C), 163.7 (1C), 153.9 (1C), 150.0 (1C), 149.7 (1C), 149.3 (1C), 149.0 (1C), 142.1 (1C), 140.8 (1C), 139.3 (1C), 132.3 (1C), 132.1 (1C), 132.0 (1C), 131.5 (2C), 128.0 (1C), 127.7 (1C), 126.5 (1C), 126.2 (2C), 126.0 (1C), 124.3 (1C), 124.1 (1C), 123.9 (2C), 123.6 (1C), 122.2 (1C), 118.0 (1C), 118,0 (2C), 117.2 (1C), 112.5 (1C), 62.0 (1C), 60.2 (1C), 55.8 (1C), 47.6 (1C), 39.8 (1C), 36.0 (1C), 35.2 (1C), 31.2 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C 47 H 44 IrN 8 O 2 S 3 1041.2379; found 1041.2385 [M-PF 6 -] + . A.12. Complex (I-l) From [(2,4-F-ppy) 2 IrCl] 2 (218.9 mg, 0.18 mmol), (I) (184.5 mg, 0.36 mmol) and Ag 2 O (83.4 mg, 0.36 mmol) in 5 mL of MeOH. Eluent CH 2 Cl 2 and MeOH (20:1). Yellow solid (187 mg, 45% yield). Anal. Calcd. For C 43 H 40 F 10 IrN 8 O 2 PS: C, 45.06; H, 3.52; N, 9.78. Found: C, 45.17; H, 3.63; N, 9.68. 1 H NMR (400 MHz, MeOD): δ 8.43-8.38 (m, 2H, H), 8.36-8.28 (m, 2H), 8.23 (dd, J = 8.4, 7.9 Hz, 1H), 8.07-8.02 (m, 1H), 8.01-7.92 (m, 2H), 7.84-7.80 (m, 1H), 7.77-7.71 (m, 1H), 7.64 (dd, J = 6.5, 1.9 Hz, 1H), 7.41 (ddd, J = 7.1, 5.6, 1.2 Hz, 1H), 7.19 (m, 2H), 6.62 (m, 2H), 5.84 (dd, J = 8.7, 2.4 Hz, 1H), 5.68 (dd, J = 7.9, 2.3 Hz, 1H), 4.49 (dd, J = 8.2, 4.1 Hz, 1H), 4.32 (td, J = 7.5, 4.4 Hz, 1H), 3.73-3.60 (m, 2H), 3.21 (m, 1H), 2.93 (ddd, J = 12.7, 11.0, 4.9 Hz, 1H), 2.82 (m, 2H), 2.71 (dd, J = 12.8, 3.9 Hz, 1H), 2.20 (t, J = 7.2 Hz, 2H), 1.81-1.36 (m, 5H), 1.39 (m, 3H). 13 C NMR (101 MHz, MeOD): δ 176.4 (1C), 174.6 (1C), 167.4 (1C), 164.4 (dd, JC-F = 230, 11 Hz, 1C), 164.8 (d, JC-F = 7 Hz, 1C), 164.7 (1C), 163.6 (d, JC-F = 7 Hz, 1C), 163.5 (dd, JC-F = 235, 12 Hz, 1C), 161.8 (dd, JC-F = 239, 11 Hz, 1C), 161.5 (dd, JC-F = 240, 12 Hz, 1C), 153.6 (1C), 153.4 (1C), 153.0 (d, JC-F = 7 Hz, 1C), 149.6 (1C), 149.4 (1C), 142.1 (1C), 139.2 (1C), 138.6 (1C), 127.9 (1C), 127.1 (1C), 124.5 (1C), 124.4 (1C), 124.2 (1C), 123.5 (2C), 123.5 (1C), 118.2 (1C), 113.0 (1C), 112.7 (d, JC-F = 21 Hz, 1C), 112.5 (d, JC-F = 21 Hz, 1C), 99.0 (t, JC-F = 27 Hz, 1C), 97.5 (t, JC-F = 27 Hz, 1C), 62.0 (2C), 60.2 (1C), 55.7 (1C), 47.7 (1C), 39.8 (1C), 35.8 (1C), 35.3 (1C), 31.4 (1C), 28.4 (1C), 28.1 (1C), 25.4 (1C). HRMS (ES + ): calcd. for C43H40F4IrN8O2S 1001.2560; found 1101.2551 [M-PF6-] + . A.13. Complex (II-a) From [(ppy) 2 IrCl] 2 (172 mg, 0.16 mmol), (II) (200 mg, 0.32 mmol) and Ag 2 O (74 mg, 0.32 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (10:1). Yellow solid (116 mg, 31% yield). Anal. Calcd. For C 55 H 58 F 6 IrN 6 OPS: C, 55.59; H, 4.92; N, 7.07. Found: C, 55.52; H, 4.81; N, 7.08. 1 H NMR (400 MHz, CDCl 3 ): δ 8.04- 7.86 (m, 6H), 7.80-7.72 (m, 2H), 7.71-7.66 (m, 3H), 7.55-7.46 (m, 2H), 7.42-7.28 (m, 2H), 7.28-7.19 (m, 2H), 7.16 (ddd, J = 7.1, 5.6, 1.4 Hz, 1H), 7.09 (ddd, J = 7.4, 5.8, 1.5 Hz, 1H), 7.08-6.98 (m, 2H), 6.95 (dd, J = 7.3, 1.3 Hz, 1H), 6.85 (dd, J = 7.5, 1.3 Hz, 1H), 6.76 (dd, J = 7.4, 1.4 Hz, 1H), 6.43 (t, J = 6.0 Hz, 1H), 6.39 (dd, J = 7.7, 1.2 Hz, 1H), 6.22 (dd, J = 7.4, 1.3 Hz, 1H), 5.33-5.22 (m, 1H), 5.09 (m, 2H), 3.67- 3.51 (m, 4H), 2.97 (m, 2H), 2.06 (m, 4H), 1.99 (m, 4H), 1.69 (m, 4H), 1.67-1.54 (m, 9H), 1.47-1.33 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ) δ 179.0 (1C), 168.6 (1C), 168.3 (1C), 167.3 (1C),163.2 (1C), 153.3 (2C), 149.8 (1C), 148.7 (2C), 144.3 (1C), 142.6 (1C), 141.7 (1C), 141.0 (1C), 138.0 (1C), 137.3 (1C), 136.5 (1C,), 135.4 (1C), 135.0 (1C), 131.1 (1C), 131.1 (2C), 130.9 (1C), 130.6 (1C), 130.4 (2C), 128.7 (1C), 126.3 (1C), 124.8 (2C), 124.3 (2C), 124.0 (2C), 123.7 (1C), 123.1 (2C), 121.6 (1C), 119.8 (2C), 118.5 (1C), 117.9 (1C), 112.8 (1C), 48.1 (1C), 39.7 (2C), 36.7 (1C), 32.6 (1C), 31.8 (1C), 26.6 (2C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C 55 H 58 IrN 6 OS 1043.4022; found 1043.4005 [M-PF 6 -] + . A.14. Complex (II-b) From [(4-Me-ppy)2IrCl]2 (90 mg, 0.08 mmol), (II) (100 mg, 0.16 mmol) and Ag2O (37 mg, 0.16 mmol) in 5 mL of MeCN. Eluent CH2Cl2 and MeOH (30:1). Yellow solid (101 mg, 52% yield). Anal. Calcd. For C57H62F6IrN6OPS: C, 56.28; H, 5.14; N, 6.91. Found: C, 56.13; H, 5.21; N, 7.05. 1 H NMR (400 MHz, CDCl3): δ 8.00 (ddd, J = 8.0, 7.4, 1.8 Hz, 1H), 7.96-7.90 (m, 3H), 7.89-7.80 (m, 2H), 7.72 (m, 3H), 7.57 (m, 2H), 7.53 (dd, J = 7.7, 1.5 Hz, 1H), 7.48 (dd, J = 5.9, 1.5 Hz, 1H), 7.40-7.30 (m, 2H), 7.27-7.20 (m, 2H), 7.17 (ddd, J = 7.0, 5.6, 1.3 Hz, 1H), 7.03 (ddd, J = 7.3, 5.8, 1.5 Hz, 1H), 6.96 (ddd, J = 7.3, 5.8, 1.4 Hz, 1H), 6.84 (dd, J = 8.0, 1.7 Hz, 1H), 6.70 (dd, J = 8.1, 1.7 Hz, 1H), 6.48 (t, J = 6.0 Hz, 1H), 6.21 (d, J = 1.7 Hz, 1H), 6.02 (d, J = 1.7 Hz, 1H), 5.33-5.17 (m, 1H), 5.10 (m, 2H), 3.55 (m, 4H), 3.00 (m, 2H), 2.08 (m, 6H), 2.04-1.89 (m, 8H), 1.69 (d, J = 1.5 Hz, 3H), 1.65-1.52 (m, 10H), 1.43 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 179.2 (1C), 168.6 (1C), 168.4 (1C), 167.4 (1C), 163.5 (1C), 153.2 (1C), 153.0 (1C), 149.8 (1C), 148.9 (1C), 148.6 (1C), 141.6 (2C), 140.9 (2C), 140.5 (1C), 140.1 (1C), 137.9 (1C), 137.1 (1C), 136.5 (1C), 135.4 (1C), 135.0 (1C), 131.9 (1C), 131.7 (1C), 131.4 (1C), 130.4 (2C), 128.6 (1C), 126.2 (1C), 124.8 (2C), 124.3 (1C), 124.2 (1C), 123.9 (2C), 123.8 (2C), 122.9 (1C), 122.4 (1C), 119.5 (2C), 118.5 (1C), 117.8 (1C), 112.6 (1C), 48.0 (1C), 39.7 (2C), 36.7 (1C), 32.6 (1C), 31.8 (1C), 26.8 (2C), 25.7 (1C), 21.9 (2C), 17.7 (1C), 16.11 (2C). HRMS (ES + ): calcd. for C 57 H 62 IrN 6 OS 1071.4335; found 1071.4344 [M-PF 6 -] + . A.15. Complex (II-c) From [(4-COOMe-ppy) 2 IrCl] 2 (137 mg, 0.11 mmol), (II) (130 mg, 0.21 mmol) and Ag 2 O (48.7 mg, 0.21 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (20:1). Orange solid (115 mg, 42% yield). Anal. Calcd. For C 59 H 62 F 6 IrN 6 O 5 PS: C, 54.33; H, 4.79; N, 6.44. Found: C, 54.18; H, 4.77; N, 6.23. 1 H NMR (400 MHz, MeOD): δ 8.35 (d, J = 2.2 Hz, 1H), 8.24 (m, 2H), 8.19-8.07 (m, 3H), 7.95 (m, 2H), 7.88 (d, J = 8.2 Hz, 1H), 7.79 (m, 3H), 7.55 (m, 2H), 7.49 (dd, J = 8.2, 1.7 Hz, 1H), 7.43 (dd, J = 7.9, 1.3 Hz, 1H), 7.34 (m, 3H), 7.24 (m, 3H), 7.08 (d, J = 1.7 Hz, 1H), 6.91 (d, J = 1.7 Hz, 1H), 5.25 (t, J = 6.4 Hz, 1H), 5.07 (m, 2H), 3.66 (m, 8H), 3.55 (d, J = 7.7 Hz, 2H), 2.84 (m, 2H), 2.09-1.88 (m, 8H), 1.65 (d, J = 1.5 Hz, 3H), 1.62-1.51 (m, 10H), 1.42 (m, 1H). 13 C NMR (101 MHz, MeOD): δ 177.9 (1C), 170.0 (1C), 167.3 (2C), 167.0 (1C), 165.9 (1C), 162.3 (1C), 153.5 (2C), 149.7 (1C), 149.4 (2C), 147.8 (2C), 141.8 (1C), 140.2 (1C), 138.7 (1C), 138.0 (1C), 137.7 (1C), 134.9 (2C), 131.3 (2C), 130.8 (1C), 130.3 (1C), 130.1 (1C), 129.9 (1C), 127.2 (1C), 125.7 (1C), 125.3 (1C), 124.6 (1C), 124.5 (1C), 124.4 (2C), 124.1 (1C), 124.0 (2C), 123.7 (2C), 122.8 (1C), 121.3 (1C), 121.1 (1C), 118.9 (1C), 118.0 (1C), 112.8 (1C), 51.2 (2C), 48.1 (1C), 39.4 (1C), 39.3 (1C), 36.2 (1C), 32.0 (1C), 31.5 (1C), 26.4 (1C), 26.0 (1C), 24.6 (1C), 16.5 (1C), 15.0 (2C). HRMS (ES + ): calcd. for C59H62IrN6O5S 1159.4123; found 1159.4130 [M-PF6-] + . A.16. Complex (II-d) From [(3-COOMe-ppy) 2 IrCl] 2 (137 mg, 0.11 mmol), (II) (130 mg, 0.21 mmol) and Ag 2 O (48.7 mg, 0.21 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (30:1). Yellow solid was filtered and dried under vacuum (57.2 mg, 21% yield). Anal. Calcd. For C 59 H 62 F 6 IrN 6 O 5 PS: C, 54.33; H, 4.79; N, 6.44. Found: C, 54.59; H, 4.60; N, 6.35. 1 H NMR (400 MHz, CDCl 3 ): δ 8.43-8.33 (m, 2H), 8.18-7.96 (m, 6H), 7.85 (m, 2H), 7.66-7.61 (m, 1H), 7.58 (m, 2H), 7.51 (dd, J = 7.6, 1.4 Hz, 1H), 7.45 (dd, J = 8.1, 1.8 Hz, 1H), 7.40-7.30 (m, 3H), 7.22 (m, 3H), 7.14 (ddd, J = 7.4, 5.8, 1.4 Hz, 1H), 6.64 (m, 1H), 6.49 (d, J = 8.1 Hz, 1H), 6.29 (d, J = 7.8 Hz, 1H), 5.31-5.16 (m, 1H), 5.13-4.97 (m, 2H), 3.88 (s, 3H), 3.84 (s, 3H), 3.60 (m, 2H), 3.51 (d, J = 7.6 Hz, 2H), 2.97 (m, 2H), 2.00 (m, 8H), 1.68 (d, J = 1.5 Hz, 3H), 1.62 (m, 10H), 1.51-1.40 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 177.7 (1C), 171.0 (1C), 168.4 (1C), 167.5 (1C), 167.4 (2C), 166.1 (1C), 157.5 (1C), 153.6 (1C), 153.2 (1C), 149.5 (1C), 149.1 (1C), 144.8 (1C), 143.2 (1C), 142.2 (1C), 140.9 (1C), 138.6 (1C), 138.0 (1C), 136.2 (1C), 135.4 (1C), 134.9 (1C), 131.4 (2C), 131.2 (2C), 130.8 (1C), 130.6 (1C), 130.5 (1C), 128.6 (1C), 126.3 (1C), 125.5 (2C), 125.3 (1C), 124.3 (4C), 124.0 (2C), 123.7 (1C), 120.3 (2C), 118.5 (1C), 118.2 (1C), 113.3 (1C), 52.0 (2C), 48.1 (1C), 40.0 (2C), 36.6 (1C), 32.5 (1C), 31.8 (1C), 26.6 (2C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C59H62IrN6O5S 1159.4123; found 1159.4109 [M- PF6-] + . A.17. Complex (II-e) From [(p-3-COOMe-ppy2IrCl]2 (137 mg, 0.11 mmol), (II) (130 mg, 0.21 mmol) and Ag2O (48.7 mg, 0.21 mmol) in 5 mL of MeCN. Eluent CH2Cl2 and MeOH (30:1). Orange solid (105 mg, 38% yield). Anal. Calcd. For C59H62F6IrN6O5PS: C, 54.33; H, 4.79; N, 6.44. Found: C, 54.19; H, 4.90; N, 6.53. 1 H NMR (400 MHz, MeOD): δ 8.51 (d, J = 1.9 Hz, 1H), 8.42-8.30 (m, 3H), 8.28 (d, J = 8.5 Hz, 2H), 8.22 (m, 2H), 8.16 (d, J = 1.8 Hz, 1H), 7.93 (m, 2H), 7.84 (dd, J = 5.6, 1.6 Hz, 1H), 7.64 (d, J = 2.2 Hz, 1H), 7.45 (dd, J = 7.9, 1.2 Hz, 1H), 7.42-7.31 (m, 3H), 7.26 (dd, J = 7.4, 1.2 Hz, 1H), 7.08 (dd, J = 7.5, 1.3 Hz, 1H), 7.01 (m, 2H), 6.90 (dd, J = 7.5, 1.4 Hz, 1H), 6.48 (dd, J = 7.7, 1.2 Hz, 1H), 6.29 (dd, J = 7.4, 1.3 Hz, 1H), 5.23 (m, 1H), 5.05 (m, 2H), 3.83 (m, 6H), 3.78-3.69 (m, 1H), 3.73-3.56 (m, 1H), 3.56 (d, J = 7.6 Hz, 2H), 2.99 (m, 2H), 1.97 (m, 8H), 1.74 (m, 1H), 1.64 (d, J = 1.5 Hz, 3H), 1.55 (m, 10H). 13 C NMR (101 MHz, MeOD): δ 178.2 (1C), 172.5 (1C), 171.0 (1C), 170.1 (1C), 164.6 (1C), 163.5 (2C), 154.2 (1C), 153.5 (1C), 150.4 (1C), 149.7 (2C), 143.4 (1C), 142.0 (1C), 141.8 (1C), 140.2 (1C), 138.7 (1C), 137.9 (2C), 134.9 (1C), 134.9 (1C), 131.8 (1C), 131.3 (1C), 131.0 (2C), 130.8 (1C), 130.2 (1C), 129.9 (1C), 127.2 (1C), 126.5 (2C), 125.9 (1C), 125.8 (1C), 125.0 (1C), 124.3 (2C), 124.0 (1C), 123.6 (1C), 123.4 (1C), 121.9 (1C), 119.7 (1C), 119.4 (1C), 118.9 (1C), 118.2 (1C), 112.9 (1C), 52.0 (2C), 47.5 (1C), 39.4 (2C), 36.2 (1C), 32.0 (1C), 31.4 (1C), 26.4 (2C), 24.6 (1C), 16.5 (1C), 15.0 (2C). HRMS (ES + ): calcd. for C 59 H 62 IrN 6 O 5 S 1159.4123; found 1159.4119 [M-PF 6 -] + . A.18. Complex (II-g) From [(pq) 2 IrCl] 2 (133.6 mg, 0.11 mmol), (II) (130 mg, 0.21 mmol) and Ag 2 O (48.7 mg, 0.21 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (10:1). Orange solid (115 mg, 43% yield). Anal. Calcd. For C 63 H 62 F 6 IrN 6 OPS: C, 58.73; H, 4.85; N, 6.52. Found: C, 58.62; H, 4.87; N, 6.40. 1 H NMR (400 MHz, CDCl 3 ): δ 8.40 (d, J = 8.9 Hz, 1H), 8.30 (d, J = 8.8 Hz, 1H), 8.18 (d, J = 8.8 Hz, 1H), 8.13-8.03 (m, 2H), 7.93 (d, J = 7.9 Hz, 1H), 7.84 (dd, J = 7.9, 1.7 Hz, 1H), 7.80-7.73 (m, 2H), 7.68 (dd, J = 8.0, 1.7 Hz, 1H), 7.62 (d, J = 8.7 Hz, 1H), 7.58-7.48 (m, 3H), 7.40-7.29 (m, 5H), 7.24-7.16 (m, 2H), 7.15-7.03 (m, 3H), 7.00-6.93 (m, 2H), 6.82 (dd, J = 7.4, 1.2 Hz, 1H), 6.68-6.57 (m, 2H), 6.51 (t, J = 6.1 Hz, 1H), 6.30 (dd, J = 7.6, 1.2 Hz, 1H), 5.34-5.22 (m, 1H), 5.09 (m, 2H), 3.66 (m, 1H), 3.55 (d, J = 7.7 Hz, 2H), 3.45 (m, 1H), 3.23 (m, 1H), 2.98 (m, 1H), 2.02 (m, 8H), 1.68 (m, 4H), 1.64-1.54 (m, 9H), 1.41- 1.33 (m, 1H). 13 C NMR (101 MHz, CDCl3): δ 179.6 (1C), 171.3 (1C), 170.7 (1C), 168.4 (1C), 164.0 (1C), 152.4 (1C), 149.4 (1C), 148.3 (1C), 147.1 (2C), 146.7 (1C), 144.7 (1C), 141.5 (1C), 140.9 (1C), 140.1 (1 C), 139.5 (1C), 136.2 (1C), 135.4 (2C), 133.2 (1C), 132.8 (1C), 131.5 (1C), 131.4 (1C), 131.2 (1C), 131.1 (2C), 130.5 (1C), 130.0 (1C), 129.2 (2C), 128.5 (1C), 127.8 (2C), 127.5 (1C), 127.0 (1C), 126.9 (1C), 126.7 (1C), 126.4 (1C), 126.0 (1C), 124.7 (1C), 124.3 (1C), 123.7 (2C), 123.5 (2C), 122.0 (1C), 118.5 (1C), 118.1 (1C), 117.8 (1C), 117.4 (1C), 112.3 (1C), 47.2 (1C), 39.7 (2C), 36.7 (1C), 32.4 (1C), 31.3 (1C), 26.8 (2C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C 63 H 62 IrN 6 OS 1143.4335; found 1143.4332 [M-PF 6 -] + . A.19. Complex (II-h) From [(piq) 2 IrCl] 2 (102 mg, 0.08 mmol), (II) (100 mg, 0.16 mmol) and Ag 2 O (37 mg, 0.16 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (10:1). Yellow solid (85 mg, 41% yield). Anal. Calcd. For C 63 H 62 F 6 IrN 6 OPS: C, 58.73; H, 4.85; N, 6.52. Found: C, 58.58; H, 4.88; N, 6.39. 1 H NMR (400 MHz, CDCl 3 ): δ 8.94 (d, J = 7.6 Hz, 1H), 8.88 (d, J = 7.5 Hz, 1H), 8.29 (d, J = 8.1 Hz, 1H), 8.21 (d, J = 8.0 Hz, 1H), 8.11-8.04 (m, 3H), 7.92 (m, 2H), 7.80-7.70 (m, 6H), 7.50-7.29 (m, 8H), 7.20 (m, 1H), 7.17-7.10 (m, 2H), 7.05-6.93 (m, 2H), 6.77 (m, 1H), 6.36 (d, J = 7.7 Hz, 1H), 6.26 (d, J = 7.4 Hz, 1H), 5.20 (t, J = 7.7 Hz, 1H), 5.08 (m, 2H), 3.58-3.33 (m, 4H), 3.07-2.96 (m, 2H), 2.08-1.89 (m, 8H), 1.68-1.49 (m, 12H), 1.34-1.24 (m, 2H). 13 C NMR (101 MHz, CDCl 3 ): δ 179.6 (1C), 170.2 (1C), 168.3 (1C), 167.9 (1C), 165.5 (1C), 153.2 (1C), 152.3 (1C), 149.5 (1C), 146.1 (1C), 145.0 (1C), 144.36 (1C), 141.7 (1C), 140.8 (2C), 136.9 (2C,), 136.5 (1C), 134.7 (1C), 131.6 (4C), 131.4 (2C), 131.0 (1C), 130.9 (2C), 130.5 (2C), 130.3 (1C), 128.7-128.6 (3C), 127.6 (1C), 127.5 (1C), 127.3 (1C), 126.7 (1C), 126.4 (2C), 126.3 (1C), 124.3 (1C), 124.0 (1C), 123.9 (1C), 123.7 (1C), 122.8 (1C), 122.7 (1C), 121.6 (1C), 121.5 (1C), 118.5 (1C), 118.2 (1C), 113.0 (1C), 47.9 (1C), 39.6 (2C), 36.7 (1C), 32.7 (1C), 31.7 (1C), 26.7 (1C), 26.4 (1C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C63H62IrN6OS 1143.4338; found 1143.4335 [M-PF6-] + . A.20. Complex (II-i) From [(bzq)2IrCl]2 (93.5 mg, 0.08 mmol), (II) (100 mg, 0.16 mmol) and Ag2O (37 mg, 0.16 mmol) in 5 mL of MeCN. Eluent CH2Cl2 and MeOH (10:1). Yellow solid (101 mg, 51% yield). Anal. Calcd. For C59H58F6IrN6OPS: C, 57.32; H, 4.73; N, 6.80. Found: C, 57.24; H, 4.75; N, 6.69. 1 H NMR (400 MHz, CDCl3): δ 8.36 (dd, J = 5.4, 1.3 Hz, 1H), 8.25 (m, 2H), 7.94-7.86 (m, 4H), 7.79 (d, J = 8.8 Hz, 1H), 7.73 (d, J = 8.8 Hz, 1H), 7.66 (dd, J = 5.5, 1.3 Hz, 1H), 7.61 (m, 2H), 7.53-7.48 (m, 1H), 7.47-7.40 (m, 3H), 7.37-7.30 (m, 2H), 7.26 (d, J = 7.9 Hz, 1H), 7.22 (m, 1H), 7.18-7.11 (m, 2H), 7.05-6.93 (m, 2H), 6.39 (dd, J = 7.3, 0.8 Hz, 1H), 6.25 (dd, J = 7.0, 1.0 Hz, 1H), 6.15 (t, J = 6.0 Hz, 1H), 5.24 (m, 1H), 5.09 (m, 2H), 3.57-3.35 (m, 4H), 2.61 (m, 2H), 2.13-1.93 (m, 8H), 1.74-1.66 (m, 3H), 1.63-1.52 (m, 9H), 1.41- 1.32 (m, 1H), 0.80-0.66 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 178.0 (1C,), 168.2 (1C), 160.6 (1C), 158.1 (1C), 156.9 (1C), 153.5 (1C), 152.2 (1C), 150.2 (1C), 147.8 (1C), 145.3 (1C), 141.7 (1C), 141.1 (1C), 140.9 (1C), 140.0 (1C), 137.1 (1C), 136.4 (2C), 135.4 (1C), 134.9 (1C), 134.4 (1C), 134.1 (1C), 131.4 (1C), 130.5 (2C), 130.1 (3C), 130.0 (1C), 128.7 (1C), 128.6 (1C), 128.4 (1C), 127.5 (1C), 127.1 (1C), 126.2 (1C), 124.3 (1C), 123.8 (5C), 123.1 (1C), 122.1 (1C), 121.1 (1C), 119.5 (1C), 118.5 (1C), 117.8 (1C), 112.7 (1C), 48.1 (1C), 39.7 (2C), 36.4 (1C), 32.5 (1C), 31.6 (1C), 26.8 (2C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C 59 H 58 IrN 6 OS 1091.4022; found 1091.4025 [M-PF 6 -] + . A.21. Complex (II-j) From [(thpy)2IrCl]2 (103 mg, 0.08 mmol), (II) (100 mg, 0.16 mmol) and Ag2O (37 mg, 0.16 mmol) in 5 mL of MeCN. Eluent CH2Cl2 and MeOH (20:1). Yellow solid (63 mg, 30% yield). Anal. Calcd. For C59H58F6IrN6OPS3: C, 54.49; H, 4.50; N, 6.46. Found: C, 54.32; H, 4.67; N, 6.38. 1 H NMR (400 MHz, MeOD) 1 H NMR (400 MHz, CDCl3): δ 8.14-7.99 (m, 3H), 7.89-7.76 (m, 6H), 7.66-7.57 (m, 3H), 7.41-7.30 (m, 2H), 7.26 (m, 2H), 7.21-7.08 (m, 3H), 7.04 (m, 1H), 6.94 (m, 1H), 6.86 (m, 2H), 6.21-6.11 (m, 2H), 5.92 (dd, J = 8.2, 3.8 Hz, 1H), 5.25 (t, J = 7.7 Hz, 1H), 5.09 (m, 2H), 3.58-3.33 (m), 2.78-2.48 (m, 2H), 2.02 (m, 8H), 1.70-1.67 (s, 3H), 1.65-1.51 (m, 9H), 1.31-1.25 (m, 2H). 13 C NMR (101 MHz, CDCl3): δ 177.1 (1C), 168.4 (1C), 165.4 (2C), 164.5 (1C), 153.8 (1C), 153.3 (1C), 150.5 (2C), 149.7 (1C), 146.6 (1C), 146.2 (1C), 145.5 (1C), 143.7 (1C), 142.5 (1C), 139.3 (2C), 138.8 (1C), 138.4 (1C), 134.4 (1C), 134.2 (1C), 133.3 (1C), 132.1 (1C), 129.7 (1C), 126.6 (1C), 126.1 (1C), 125.7 (1C), 125.6 (2C), 125.2 (3C), 124.7 (1C), 124.4 (1C), 124.3 (2C), 124.0 (1C), 123.4 (1C), 123.1 (2C), 122.3 (1C), 120.6 (1C), 120.5 (1C), 119.9 (1C), 119.5 (1C), 119.0 (1C), 113.7 (1C), 47.9 (1C), 40.5 (2C), 38.3 (1C), 32.6 (1C), 31.8 (1C), 29.7 (2C), 29.4 (1C), 22.7 (1C), 14.1 (2C). HRMS (ES + ): calcd. for C 59 H 58 IrN 6 OS 3 1155.3463; found 1155.3479 [M-PF 6 -] + . A.22. Complex (II-k) From [(pbt)2IrCl]2 (155.6 mg, 0.12 mmol), (II) (150 mg, 0.24 mmol) and Ag2O (55.6 mg, 0.24 mmol) in 5 mL of MeCN. Eluent CH2Cl2 and MeOH (20:1). Yellow solid (97 mg, 31% yield). Anal. Calcd. For C59H58F6IrN6OPS3: C, 54.49; H, 4.50; N, 6.46. Found: C, 54.36; H, 4.62; N, 6.35. 1 H NMR (400 MHz, CDCl3): δ 8.11 (m, 3H), 7.93-7.84 (m, 2H), 7.84-7.74 (m, 3H), 7.56-7.29 (m, 7H), 7.26-7.18 (m, 2H), 7.17-7.03 (m, 2H), 7.01-6.89 (m, 2H), 6.79-6.69 (m, 1H), 6.55 (s, 1H), 6.38 (m, 3H), 6.06 (d, J = 8.4 Hz, 1H), 5.29-5.19 (m, 1H), 5.16-5.02 (m, 2H), 3.67-3.54 (m, 2H), 3.50 (d, J = 7.6 Hz, 2H), 3.05-2.95 (m, 2H), 2.11-1.89 (m, 8H), 1.77-1.65 (m, 4H), 1.65-1.43 (m, 10H). 13 C NMR (101 MHz, CDCl 3 ): δ 182.7 (1C), 179.6 (1C), 175.5 (1C), 168.4 (1C), 163.6 (1C), 153.8 (1C), 150.1 (1C), 149.7 (1C), 149.1 (2C), 142.3 (1C), 140.6 (1C), 139.1 (1C), 132.4 (3C), 131.8 (1C), 131.0 (2C), 130.4 (1C), 128.7 (1C), 128.3 (1C), 126.7 (1C), 126.4 (2C), 126.1 (1C), 124.3 (1C), 124.0 (1C), 123.7 (2C), 123.5 (2C), 122.5 (1C), 118.4 (2C), 117.6 (1C), 113.0 (1C), 48.0 (1C), 39.7 (2C), 36.6 (1C), 32.7 (1C), 31.5 (1C), 26.8 (2C), 25.7 (1C), 17.7 (1C), 16.1 (2C). HRMS (ES + ): calcd. for C 59 H 58 IrN 6 OS 3 1155.3463; found 1155.3483 [M-PF 6 -] + . A.23. Complex (II-l) From [(2,4-F-ppy) 2 IrCl] 2 (146 mg, 0.12 mmol), (II) (150 mg, 0.24 mmol) and Ag 2 O (55.6 mg, 0.24 mmol) in 5 mL of MeCN. Eluent CH 2 Cl 2 and MeOH (10:1). Yellow solid (108 mg, 36% yield). Anal. Calcd. For C55H54F10IrN6OPS: C, 52.42; H, 4.32; N, 6.67. Found: C, 52.32; H, 4.45; N, 6.53. 1 H NMR (400 MHz, CDCl3) δ 8.38- 8.32 (m, 1H), 8.32-8.27 (m, 1H), 8.18-8.06 (m, 2H), 8.04 (d, J = 2.2 Hz, 1H), 7.94 (dd, J = 6.0, 1.6 Hz, 1H), 7.82 (m, 2H), 7.71 (dd, J = 5.6, 1.2 Hz, 1H), 7.60-7.50 (m, 2H), 7.40-7.31 (m, 3H), 7.30-7.21 (m, 2H), 7.17 (ddd, J = 7.4, 5.8, 1.4 Hz, 1H), 7.09 (ddd, J = 7.4, 5.9, 1.4 Hz, 1H), 6.72 (t, J = 6.0 Hz, 1H), 6.56 (ddd, J = 12.6, 8.9, 2.4 Hz, 1H), 6.47 (ddd, J = 12.4, 9.0, 2.4 Hz, 1H), 5.79 (dd, J = 8.5, 2.3 Hz, 1H), 5.63 (dd, J = 7.7, 2.4 Hz, 1H), 5.25 (t, J = 7.1 Hz, 1H), 5.14-5.04 (m, 2H), 3.66 (d, J = 6.7, Hz, 2H), 3.52 (d, J = 7.7 Hz, 2H), 3.12 (dd, J = 13.3, 6.7 Hz, 2H), 2.01 (m, 8H), 1.69 (d, J = 1.4 Hz, 3H), 1.63-1.51 (m, 11H). 13 C NMR (101 MHz, CDCl3): δ 176.4 (1C), 168.4 (1C), 167.4 (1C), 164.9 (d, JC-F = 7 Hz, 1C), 164.3 (dd, JC-F = 259, 11 Hz, 1C), 163.8 (d, J C-F = 7 Hz, 1C), 163.5 (dd, J C-F = 258, 11 Hz, 1C), 161.7 (dd, J C-F = 263, 11 Hz, 1C), 161.4 (dd, J C-F = 261, 13 Hz, 1C), 153.5 (1C), 153.1 (1C), 152.4 (d, J C-F = 7 Hz, 1C), 149.4 (1C), 149.0 (1C), 142.4 (1C), 140.9 (1C), 138.9 (1C), 138.3 (1C), 136.2 (1C), 135.4 (1C), 134.8 (1C), 131.4 (1C), 130.8 (1C), 130.5 (1C), 128.8 (1C), 127.9 (1C), 126.9 (1C), 126.4 (1C), 124.8 (1C), 124.4 (1C), 124.4 (1C), 124.3 (1C), 124.0 (1C), 123.8 (1C), 123.7 (1C), 123.5 (1C), 118.5 (1C), 118.3 (1C), 113.5 (1C), 113.1 (d, J C-F = 17 Hz, 1C), 113.0 (d, J C-F = 17 Hz, 1C), 99.7 (t, J C-F = 27 Hz, 1C), 98.2 (t, J C-F = 27 Hz, 1C), 48.2 (1C), 39.7 (1C), 39.6 (1C), 36.7 (1C), 32.7 (1C), 31.9 (1C), 26.7 (1C), 26.4 (1C), 25.7 (1C), 17.7 (1C), 16.1 (1C), 16.0 (1C). HRMS (ES + ): calcd. for C 55 H 54 IrN 6 OS 1115.3645; found 1115.3660 [M-PF 6 -] + . B. Synthesis of complexes (III-a-b), (III-d-e), (III-g-l) and (IV-a) to (IV-l). The iridium(III) dimers [(C^N) 2 IrCl] 2 were prepared according to literature procedures [6,7]. B.1. General protocol for the synthesis of complexes (III-a-b), (III-d-e), (III- g-l) and (IV-a) to (IV-l) A mixture of two equivalents of (III) or (IV), two equivalents of silver oxide and one equivalent of [(C^N) 2 IrCl] 2 in MeOH for (III) or MeCN for (IV) (10 mL) was refluxed for 12 h. After cooling down to room temperature, an aqueous solution of NH4PF6 (200 mg in 10 mL deionized water) was slowly added into the reaction mixture under stirring, resulting in a yellow suspension. The suspension was then filtered and the resulting precipitate was washed with deionized water and dried under vacuum at 70°C for 12 h. The crude product was purified by column chromatography (SiO2) with CH2Cl2/MeOH (10:1) as the eluent, yielding a solid. B.2. Complex (III-a) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(ppy)2IrCl]2 (0.089 g, 0.083 mmol). Yellow solid (0.041 g, 21%). Anal. Calcd. For C45H46F6IrN8O8P: C, 46.43; H, 3.98; N, 9.63. Found: C, 46.21; H, 4.02; N, 9.51. 1 H NMR (600 MHz, MeOD + CD 2 Cl 2 ): δ 8.25 (d, J = 2.2 Hz, 1H), 8.19-8.14 (m, 2H), 8.12 (dd, J = 13.7, 6.2 Hz, 1H), 8.08 (d, J = 4.4 Hz, 1H), 8.07 (s, 1H), 7.90 (dd, J = 4.5, 2.9 Hz, 1H), 7.88 (d, J = 7.9 Hz, 1H), 7.81 (d, J = 7.7 Hz, 2H), 7.79-7.73 (m, 1H), 7.65 (dd, J = 8.8, 5.1 Hz, 1H), 7.42-7.35 (m, 1H), 7.27 (t, J = 6.5 Hz, 1H), 7.11 (ddd, J = 6.0, 4.4, 2.7 Hz, 1H), 7.10-7.06 (m, 1H), 7.05-7.01 (m, 1H), 6.97-6.91 (m, 2H), 6.85- 6.80 (m, 1H), 6.45 (dd, J = 7.5, 4.4 Hz, 1H), 6.23 (d, J = 7.4 Hz, 1H), 4.41-4.28 (m, 1H), 4.19-4.06 (m, 1H), 3.81 (m, 2H), 3.23-2.79 (m, 2H), 2.70-2.35 (m, 2H), 2.32- 2.06 (m, 4H), 1.96-1.65 (m, 2H), 1.54-1.42 (m, 2H), 1.42-1.30 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 179.4 (1C), 179.3 (1C), 175.5 (1C), 175.0 (1C), 170.3 (1C), 168.8 (1C), 167.5 (1C), 163.0 (1C), 158.2 (1C), 153.6 (1C), 153.4 (1C), 149.4 (1C), 148.7 (1C), 148.6 (1C), 144.6 (1C), 142.8 (1C), 141.4 (1C), 138.9 (1C), 137.4 (1C), 130.9 (1C), 130.7 (1C), 130.2 (1C), 129.8 (1C), 127.8 (1C), 124.6 (1C), 124.6 (1C), 123.9 (1C), 123.8 (1C), 123.7 (1C), 122.7 (1C), 121.3 (1C), 119.7 (1C), 119.7 (1C), 117.7 (1C), 117.5 (1C), 56.6 (1C), 55.3 (1C), 45.8 (1C), 38.7 (1C), 36.6 (1C), 34.9 (1C), 30.5 (1C), 28.5 (1C), 25.5 (1C), 21.3 (1C). HRMS (ES + ): calcd. for C 45 H 44 N 8 O 7 Ir 1001.2965; found 1001.2946 [M-PF 6 --H 2 O] + . B.3. Complex (III-b) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(4-Me-ppy)2IrCl]2 (0.094 g, 0.083 mmol). Yellow solid (0.038 g, 19%). Anal. Calcd. For C47H50F6IrN8O8P: C, 47.35; H, 4.23; N, 9.40. Found: C, 47.21; H, 4.23; N, 9.26. 1 H NMR (400 MHz, MeOD): δ 8.25 (d, J = 2.2 Hz, 1H), 8.12-8.03 (m, 3H), 7.99 (m, 2H), 7.9-7.80 (m, 2H), 7.78 (d, J = 5.3 Hz, 1H), 7.70-7.63 (m, 2H), 7.60 (d, J = 5.4 Hz, 1H), 7.35 (d, J = 2.2 Hz, 1H), 7.28 (ddd, J = 7.0, 5.5, 1.3 Hz, 1H), 7.04 (dd, J = 14.2, 7.0 Hz, 2H), 6.86 (d, J = 8.0 Hz, 1H), 6.77 (d, J = 7.8 Hz, 1H), 6.25 (s, 1H), 6.04 (s, 1H), 4.30-4.15 (m, 2H), 3.94-3.70 (m, 2H), 3.15-3.03 (m, 2H), 2.49-2.34 (m, 2H), 2.13 (t, J = 6.2 Hz, 2H), 2.05 (s, 3H), 2.04 (s, 3H), 1.98-1.87 (m, 2H), 1.85-1.58 (m, 2H), 1.51-1.42 (m, 2H), 1.42-1.32 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 179.6 (1C), 176.2 (1C), 175.8 (2C), 170.2 (1C), 168.8 (1C), 167.4 (1C), 163.7 (1C), 158.8 (1C), 153.5 (1C), 153.1 (1C), 149.5 (1C), 148.9 (1C), 148.6 (1C), 142.0 (1C), 141.3 (1C), 140.4 (1C), 140.3 (1C), 140.0 (1C), 137.9 (1C), 137.2 (1C), 131.5 (1C), 131.4 (1C), 124.6 (2C), 123.8 (1C), 123.7 (1C), 123.7 (1C), 123.3 (1C), 122.3 (1C), 122.2 (1C), 119.4 (2C), 117.5 (1C), 112.4 (1C), 53.4 (1C), 53.1 (1C), 45.7 (1C), 38.8 (1C), 36.6 (1C), 32.1 (1C), 30.2 (1C), 28.5 (1C), 28.1 (1C), 22.8 (1C), 20.5 (2C). HRMS (ES + ): calcd. for C 47 H 50 N 8 O 8 Ir 1047.3384; found 1047.3405 [M-PF 6 -] + . B.4. Complex (III-d) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(3-COOMe-ppy) 2 IrCl] 2 (0.108 g, 0.083 mmol). Yellow solid (0.082 g, 39%). Anal. Calcd. For C 49 H 50 F 6 IrN 8 O 12 P: C, 45.97; H, 3.94; N, 8.75. Found: C, 46.09; H, 4.01; N, 8.83. 1 H NMR (600 MHz, MeOD): δ 8.50-8.43 (m, 2H), 8.34-8.29 (m, 2H), 8.26-8.19 (m, 2H), 8.18-8.14 (m, 1H), 8.13-8.06 (m, 1H), 8.03-7.93 (m, 2H), 7.74-7.68 (m, 2H), 7.59-7.53 (m, 1H), 7.46-7.41 (m, 2H), 7.33-7.26 (m, 1H), 7.24-7.16 (m, 2H), 6.61-6.53 (m, 1H), 6.38-6.30 (m, 1H), 4.65-4.05 (m, 2H), 3.86 (s, 2H), 3.84-3.70 (m, 3H), 3.37 (s, 3H), 3.13-2.98 (m, 2H), 2.67-1.58 (m, 8H), 1.48-1.40 (m, 2H), 1.40- 1.28 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 178.0 (1C), 175.8 (2C), 171.5 (1C), 169.9-169.8 (2C), 167.8 (2C), 167.4 (1C), 166.2 (1C), 158.7 (1C), 157.8 (1C), 153.4 (2C), 149.2-149.4 (2C), 145.3 (1C), 143.6 (1C), 141.8 (1C), 138.8 (1C), 138.2 (1C), 131.1(2C), 130.6 (1C), 130.1(1C), 125.0 (3C), 124.9 (1C), 124.1-124.1 (2C), 123.8 (1C), 123.6 (1C), 120.4 (2C), 117.9 (1C), 112.9 (1C), 54.0 (1C), 53.2 (1C), 51.1 (1C), 48.5 (1C), 45.9 (1C), 38.7 (1C), 36.2 (1C), 32.5 (1C), 30.2 (1C), 28.4 (1C), 28.1 (1C), 22.6 (1C). HRMS (ES + ): calcd. for C49H50N8O12Ir 1135.3154; found 1135.3181 [M- PF6-] + . B.5. Complex (III-e) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(p-3-COOMe-ppy)2IrCl]2 (0.108 g, 0.083 mmol). Yellow solid (0.092 g, 43%). Anal. Calcd. For C49H50F6IrN8O12P: C, 45.97; H, 3.94; N, 8.75. Found: C, 45.88; H, 3.75; N, 8.57. 1 H NMR (600 MHz, MeOD): δ 8.48-8.34 (m, 5H), 8.34-8.28 (m, 2H), 8.24-8.18 (m, 1H), 8.16-8.11 (m, 1H), 7.97-7.91 (m, 2H), 7.84-7.80 (m, 1H), 7.51-7.42 (m, 1H), 7.41-7.33 (m, 1H), 7.14-7.08 (m, 1H), 7.05-6.98 (m, 2H), 6.94-6.84 (m, 1H), 6.48-6.42 (m, 1H), 6.28-6.24 (m, 1H), 4.62-4.26 (m, 2H), 3.91 (s, 3H), 3.82 (s, 3H), 3.79-3.60 (m, 2H), 3.20-2.99 (m, 2H), 2.68-1.65 (m, 8H), 1.57-1.07 (m, 4H). 13 C NMR (151 MHz, MeOD): δ 179.2 (1C), 178.2 (1C), 177.6 (2C), 172.5 (1C), 171.0 (2C), 169.9 (1C), 164.8 (1C), 163.8 (2C), 154.3 (1C), 153.6 (1C), 152.3 (1C), 150.2 (1C), 149.7 (2C), 143.4 (1C), 142.0 (2C), 138.5 (1C), 137.8 (1C), 131.8 (1C), 131.1 (1C), 130.9 (1C), 130.7 (1C), 126.2 (2C), 125.9 (1C), 124.9 (1C), 124.2 (1C), 123.2 (1C), 121.8 (1C), 119.3 (1C), 118.2 (2C), 113.1 (1C), 60.8 (1C), 55.2 (1C), 51.8 (1C), 48.5 (1C), 45.8 (1C), 39.0 (1C), 36.9 (1C), 34.7 (1C), 32.7 (1C), 30.6 (1C), 28.4 (1C), 22.1 (1C). HRMS (ES + ): calcd. for C 49 H 48 N 8 O 11 Ir 1117.3075; found 1117.3080 [M- PF 6 --H 2 O] + . B.6. Complex (III-g) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(pq) 2 IrCl] 2 (0.106 g, 0.083 mmol). Yellow solid (0.084 g, 40%). Anal. Calcd. For C 53 H 50 F 6 IrN 8 O 8 P: C, 50.35; H, 3.99; N, 8.86. Found: C, 50.45; H, 4.09; N, 8.71. 1 H NMR (600 MHz, MeOD): δ 8.55-8.49 (m, 1H), 8.46-8.42 (m, 1H), 8.30 (d, J = 8.8 Hz, 1H), 8.24 (d, J = 8.8 Hz, 1H), 8.07 (dd, J = 8.4, 5.6 Hz, 1H), 8.03-7.98 (m, 2H), 7.94 - 7.91 (m, 2H), 7.81-7.76 (m, 3H), 7.74-7.66 (m, 1H), 7.46-7.40 (m, 3H), 7.36 (m, 1H), 7.19-7.13 (m, 2H), 7.06-6.96 (m, 3H), 6.76 (m, 1H), 6.71-6.65 (m, 1H), 6.63 (dd, J = 7.8, 2.2 Hz, 1H), 6.21 (dd, J = 7.6, 5.2 Hz, 1H), 4.63-4.07 (m, 2H), 3.92-3.64 (m, 2H), 3.13-2.99 (m, 2H), 2.64-1.60 (m, 8H), 1.48-1.32 (m, 4H). 13 C NMR (151 MHz, MeOD): δ 179.9 (1C), 177.8 (1C), 177.5 (2C), 171.6 (1C), 170.8 (1C), 169.8 (1C), 164.1 (1C), 152.7 (1C), 152.6 (1C), 149.4 (1C), 148.3 (1C), 147.1 (1C), 147.0 (1C), 146.8 (1C), 144.8 (1C), 141.4 (1C), 140.1 (1C), 139.7 (1C), 132.6 (1C), 132.4 (1C), 131.3 (1C), 130.7 (1C), 130.6 (1C), 130.5 (1C), 129.2 (1C), 129.1 (1C), 128.0 (1C), 127.9 (1C), 127.1 (1C), 126.8 (1C,), 126.7 (1C), 126.5 (1C), 126.4 (1C), 124.6 (1C), 123.7 (1C), 123.4 (1C), 123.2 (1C), 121.6 (1C), 117.9 (1C), 117.8 (1C), 117.5 (1C), 112.2 (1C), 55.2 (1C), 54.7 (1C), 45.1 (1C), 38.9 (1C), 35.6 (1C), 32.4 (1C), 31.9 (1C), 28.6 (1C), 22.7 (1C), 22.0 (1C). HRMS (ES + ): calcd. for C53H50N8O8Ir 1119.3385; found 1119.3365 [M-PF 6 -] + . B.7. Complex (III-h) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(piq) 2 IrCl] 2 (0.106 g, 0.083 mmol). Yellow solid (0.078 g, 37%). Anal. Calcd. For C 53 H 50 F 6 IrN 8 O 8 P: C, 50.35; H, 3.99; N, 8.86. Found: C, 50.41; H, 3.75; N, 8.49. 1 H NMR (400 MHz, MeOD): δ 9.03 (d, J = 7.0 Hz, 1H), 8.95 (d, J = 8.5 Hz, 1H), 8.38 (d, J = 8.2 Hz, 1H), 8.30 (m, 1H), 8.28 (d, J = 8.0 Hz, 1H), 8.25-8.20 (m, 1H), 8.13 (m, 1H), 8.02 (d, J = 7.7 Hz, 2H), 7.91-7.77 (m, 5H), 7.59 (d, J = 6.9 Hz, 1H), 7.54 (d, J = 6.2 Hz, 1H), 7.50 (dd, J = 6.6, 2.5 Hz, 1H), 7.47 (d, J = 6.5 Hz, 1H), 7.43-7.36 (m, 1H), 7.29-7.22 (m, 1H), 7.13 (dd, J = 7.8 Hz, 1H), 7.06 (dd, J = 7.8 Hz, 1H), 6.93 (dd, J = 7.5 Hz, 1H), 6.80 (dd, J = 7.5 Hz, 1H), 6.43 (d, J = 7.5 Hz, 1H), 6.20 (d, J = 7.5 Hz, 1H), 4.36-4.10 (m, 2H), 3.78-3.57 (m, 2H), 3.09-2.98 (m, 2H), 2.47-2.32 (m, 2H), 2.20-2.11 (m, 2H), 2.09-1.98 (m, 2H), 1.93-1.53 (m, 2H), 1.45-1.38 (m, 2H), 1.35- 1.29 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 179.9 (2C), 176.2 (1C), 175.8 (2C), 170.1 (1C), 170.07 (1C), 168.0 (1C), 165.6 (1C), 158.8 (1C), 153.5 (1C), 152.2 (1C), 149.3 (1C), 146.1 (1C), 144.8 (1C), 144.2 (1C), 141.4 (1C), 140.9 (1C), 137.0 (1C), 136.6 (1C), 131.6 (1C), 131.4 (2C), 131.1 (1C), 130.6 (1C), 130.4 (2C), 129.7 (1C), 128.6 (2C), 127.3 (1C), 127.2 (1C), 126.9 (1C), 126.4 (2C), 126.3 (1C), 123.9 (1C), 123.7 (1C), 122.4 (1C), 122.3 (1C), 121.1 (1C), 120.9 (1C), 117.3 (1C), 112.6 (1C), 53.0 (2C), 45.6 (1C), 38.6 (1C), 36.8 (1C), 32.1 (1C), 30.1 (1C), 28.3 (1C), 22.5 (1C). HRMS (ES + ): calcd. for C53H50N8O8Ir 1119.3385; found 1119.3390 [M-PF6-] + . B.8. Complex (III-i) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(bzq)2IrCl]2 (0.097 g, 0.083 mmol). Yellow solid (0.075 g, 37%). Anal. Calcd. For C49H46F6IrN8O8P: C, 48.55; H, 3.83; N, 9.24. Found: C, 48.57; H, 3.77; N, 9.36. 1 H NMR (400 MHz, MeOD): δ 8.56-8.43 (m, 3H), 8.37-8.19 (m, 2H), 8.14-8.05 (m, 2H), 7.88 (dd, J = 8.9, 4.0 Hz, 2H), 7.83-7.78 (m, 1H), 7.73 (m, 2H), 7.65-7.47 (m, 3H), 7.41 (dd, J = 7.7, 3.0 Hz, 1H), 7.39-7.31 (m, 1H), 7.17 (m, 2H), 7.07 (dd, J = 7.5, 3.6 Hz, 1H), 6.41 (d, J = 7.0 Hz, 1H), 6.23 (d, J = 7.0 Hz, 1H), 4.45-4.01 (m, 2H), 3.73- 3.51 (m, 2H), 3.20-2.95 (m, 2H), 2.57-1.58 (m, 8H), 1.50-1.38 (m, 2H), 1.38-1.23 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 178.3 (1C), 177.3 (1C), 175.3 (1C), 174.0 (1C), 170.2 (1C), 160.9 (1C), 158.0 (1C), 158.0 (1C), 156.9 (1C), 154.0 (1C), 152.4 (1C), 150.0 (1C), 148.1 (1C), 145.1 (1C), 141.4 (1C), 141.1 (1C), 139.9 (1C), 137.1 (1C), 136.3 (1C), 134.6 (1C), 134.4 (1C), 129.7 (1C), 129.6 (2C), 129.2 (1C), 128.3 (1C), 128.0 (1C), 127.6 (1C), 127.4 (1C,), 123.8, 123.7, 123.6, 123.5 (4C), 122.7 (1C), 121.7 (1C), 120.7 (1C), 119.1 (1C), 117.8 (1C), 112.6 (1C), 56.5 (1C), 54.8 (1C), 45.7 (1C), 38.8 (1C), 36.3 (1C), 32.1 (1C), 30.5 (1C), 28.3 (1C), 24.6 (1C), 22.5 (1C). HRMS (ES + ): calcd. for C 49 H 46 N 8 O 8 Ir 1067.3071; found 1067.3074 [M-PF 6 -] + . B.9. Complex (III-j) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(thpy) 2 IrCl] 2 (0.108 g, 0.083 mmol). Yellow solid (0.098 g, 46%). Anal. Calcd. For C 49 H 46 F 6 IrN 8 O 8 PS 2 : C, 46.11; H, 3.63; N, 8.78. Found: C, 46.21; H, 3.79; N, 8.63. 1 H NMR (400 MHz, MeOD): δ 8.39-8.36 (d, J = 2.4 Hz, 1H), 8.33-8.19 (m, 1H), 8.12- 8.04 (m, 2H), 7.98-7.88 (m, 2H), 7.81 (d, J = 8.2 Hz, 1H), 7.76-7.68 (m, 5H), 7.44- 7.37 (m, 1H), 7.18-7.10 (m, 3H), 7.10-6.95 (m, 2H), 6.89-6.84 (m, 1H), 6.81 (dd, J = 7.7 Hz, 1H), 6.21-6.15 (m, 1H), 5.98-5.94 (m, 1H), 4.63-4.57 (m, 1H), 4.26-4.04 (m, 1H), 3.82-3.65 (m, 2H), 3.09-2.91 (m, 2H), 2.69-1.48 (m, 8H), 1.45-1.37 (m, 2H), 1.31-1.29 (m, 2H). 13 C NMR (151 MHz, MeOD): δ 177.7, 177.6, 177.4 (3C), 173.7 (1C), 169.9 (1C), 165.3 (1C), 164.6 (1C), 162.4 (1C), 154.3 (1C), 153.5 (1C), 152.6 (1C), 150.1, 149.6 (2C), 146.2 (2C), 145.4 (1C), 143.6 (1C), 142.6 (1C), 142.0 (1C), 139.5 (1C), 138.7 (2C), 134.1 (1C), 125.5 (1C), 125.2 (1C), 125.0 (2C), 124.2 (2C), 123.9 (1C), 123.7 (1C), 122.8 (1C), 122.6 (1C), 122.0 (1C), 120.4 (1C), 119.5 (1C), 119.4 (1C), 118.2 (1C), 113.1 (1C), 60.9 (1C), 55.3 (1C), 46.2 (1C), 38.7 (1C), 36.2 (1C), 32.6 (1C), 32.0 (1C), 28.3 (1C), 22.4 (1C), 22.1 (1C). HRMS (ES + ): calcd. for C49H46N8O8S2Ir 1131.2404; found 1131.2510 [M-PF6-] + . B.10. Complex (III-k) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(pbt)2IrCl]2 (0.108 g, 0.083 mmol). Yellow solid (0.108 g, 51%). Anal. Calcd. For C 49 H 46 F 6 IrN 8 O 8 PS 2 : C, 46.11; H, 3.63; N, 8.78. Found: C, 46.22; H, 3.79; N, 8.63. 1 H NMR (400 MHz, MeOD): δ 8.40 (d, J = 2.4 Hz, 1H), 8.24 (ddd, J = 7.7, 7.1, 3.9 Hz, 1H), 8.19- 8.14 (m, 1H), 8.11 (d, J = 8.1 Hz, 1H), 8.03 (dd, J = 8.1, 3.9 Hz, 1H), 7.91 (dd, J = 7.7, 3.3 Hz, 1H), 7.89-7.84 (m, 2H), 7.62-7.54 (m, 1H), 7.50-7.41 (m, 2H), 7.41-7.32 (m, 2H), 7.17-7.07 (m, 2H), 7.00 (dd, J = 7.5 Hz, 1H), 6.94 (dd, J = 7.4 Hz, 1H), 6.80 (dd, J = 7.5 Hz, 1H), 6.48-6.40 (m, 2H), 6.34 (d, J = 7.5 Hz, 1H), 6.17 (dd, J = 8.5, 5.4 Hz, 1H), 4.13 (m, 2H), 3.93-3.74 (m, 2H), 3.01 (m, 2H), 2.32 (m, 2H), 2.29-2.10 (m, 2H), 2.10-1.82 (m, 2H), 1.67 (m, 2H), 1.35-1.21 (m, 4H). 13 C NMR (151 MHz, MeOD): δ 183.1 (1C), 180.2 (1C), 178.4 (1C), 175.8 (1C), 169.8 (3C), 163.8 (1C), 158.6 (1C), 154.0 (1C), 149.9 (1C), 149.7 (1C), 149.0 (2C), 142.0 (1C), 140.8 (1C), 139.3 (1C), 132.2 (1C), 132.1 (1C), 131.9 (1C), 131.6 (1C), 131.4 (1C), 131.3 (1C), 128.2 (1C), 127.5 (1C), 126.4 (1C), 126.1 (1C), 126.0 (1C), 125.7 (1C), 123.9 (1C), 123.7 (2C), 123.6 (1C), 123.5 (1C), 122.1 (1C), 118.1 (1C), 117.2 (2C), 112.6 (1C), 55.2 (2C), 45.8 (1C), 38.8 (1C), 35.9 (1C), 33.2 (1C), 33.0 (1C), 29.9 (1C), 28.6 (1C), 22.6 (1C). HRMS (ES + ): calcd. for C 49 H 46 N 8 O 8 IrS 2 1131.2510; found 1131.2511 [M-PF 6 -] + . B.11. Complex (III-l) From (III) (0.100 g, 0.167 mmol), silver oxide (0.039 g, 0.167 mmol) and [(2,4-F-ppy)2IrCl]2 (0.101 g, 0.083 mmol). Yellow solid (0.115 g, 56%). Anal. Calcd. For C45H42F10IrN8O8P: C, 43.73; H, 3.43; N, 9.07. Found: C, 43.63; H, 3.38; N, 8.94. 1 H NMR (600 MHz, MeOD): δ 8.41 (d, J = 8.6 Hz, 1H), 8.37-8.31 (m, 2H), 8.29-8.18 (m, 2H), 8.12-8.06 (m, 1H), 7.96 (m, 2H), 7.82-7.78 (m, 1H), 7.72 (dd, J = 6.5, 2.9 Hz, 1H), 7.49 (m, 1H), 7.41-7.36 (m, 1H), 7.22-7.13 (m, 2H), 6.66-6.60 (m, 1H), 6.60-6.52 (m, 1H), 5.85 (dd, J = 8.3, 2.5 Hz, 1H), 5.65 (dd, J = 8.0, 1.9 Hz, 1H), 4.56- 4.48 (m, 1H), 4.30-4.18 (m, 1H), 3.92-3.81 (m, 2H), 3.17-3.03 (m, 2H), 2.70-2.35 (m, 2H), 2.34-2.19 (m, 2H), 2.18-2.01 (m, 2H), 1.97-1.57 (m, 2H), 1.50-1.41 (m, 2H), 1.40-1.30 (m, 2H). 13 C NMR (151 MHz, MeOD): 176.6 (1C), 175.8 (1C), 175.4 (1C), 175.1 (1C), 169.8 (1C), 168.1 (1C), 164.7 (d, JC-F = 6 Hz, 1C), 164.2 (dd, JC-F = 258, 11 Hz, 1C), 163.7 (d, J C-F = 6 Hz, 1C), 163.5 (dd, J C-F = 258, 11 Hz, 1C), 161.9 (dd, J C-F = 260, 12 Hz, 1C), 161.6 (dd, J C-F = 260, 12 Hz, 1C), 158.7 (1C), 153.7 (1C), 153.4 (1C), 152.7 (1C), 149.5 (1C), 149.4 (1C), 142.1 (1C), 139.1 (1C), 138.4 (1C), 127.9 (1C), 127.0 (1C), 124.5 (1C), 124.3 (1C), 124.0 (1C), 123.6 (2C), 123.4 (1C), 118.1 (1C), 113.0 (1C), 112.7 (d, J C-F = 18 Hz, 1C), 112.4 (d, J C-F = 18 Hz, 1C), 98.9 (t, J C-F = 27 Hz, 1C), 97.5 (t, J C-F = 27 Hz, 1C), 56.6 (1C), 52.9 (1C), 46.0 (1C), 38.7 (1C), 36.2 (1C), 32.1 (1C), 30.1 (1C), 28.3 (1C), 28.0 (1C), 22.6 (1C). HRMS (ES + ): calcd. for C 45 H 40 N 8 O 7 F 4 Ir 1073.2562; found 1073.2584 [M-PF 6 --H 2 O] + . B.12. Complex (IV-a) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(ppy) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.077 g, 61%). Anal. Calcd. For C 44 H 38 F 6 FeIrN 6 OP: C, 49.86; H, 3.61; N, 7.93. Found: C, 49.69; H, 3.47; N, 7.81. 1 H NMR (400 MHz, CDCl 3 ): δ 8.95 (s, 1H), 8.87 (d, J = 8.3 Hz, 1H), 8.39 (s, 1H), 8.23 (t, J = 5.7 Hz, 1H), 8.02 (td, J = 7.8, 1.7 Hz, 1H), 7.95 (d, J = 8.2 Hz, 1H), 7.91-7.85 (m, 2H), 7.78-7.71 (m, 2H), 7.71-7.64 (m, 3H), 7.46 (d, J = 5.8 Hz, 1H), 7.15-7.08 (m, 1H), 7.08-7.00 (m, 2H), 7.00-6.91 (m, 3H), 6.90-6.81 (m, 1H), 6.35 (d, J = 7.7 Hz, 1H), 6.26 (d, J = 7.3 Hz, 1H), 5.21 (d, J = 1.2 Hz, 1H), 5.16 (d, J = 1.3 Hz, 1H), 4.24 (dd, J = 3.2 Hz, 2H), 4.14 (s, 5H), 3.75 (t, J = 7.1 Hz, 2H), 3.11-2.90 (m, 2H), 1.60- 1.43 (m, 2H). 13 C NMR (101 MHz, CDCl3): δ 178.2 (1C), 170.9 (1C), 168.9 (1C), 167.7 (1C), 163.7 (1C), 153.9 (1C), 153.1 (1C), 149.5 (1C), 148.6 (1C), 148.4 (1C), 144.2 (1C), 142.3 (1C), 141.5 (1C), 137.7 (1C), 137.0 (1C), 131.1 (1C), 130.9 (2C), 130.6 (1C), 125.7 (1C), 124.9 (1C), 124.7 (1C), 124.0 (1C), 123.4 (1C), 123.0 (1C), 122.6 (1C), 121.9 (1C), 119.8 (1C), 119.6 (1C), 118.6 (1C), 114.0 (1C), 76.4 (1C), 70.3 (1C), 70.2 (1C), 69.7 (5C), 69.1 (2C), 47.8 (1C), 36.1 (1C), 32.1 (1C). HRMS (ES + ): calcd. for C44H38N6OFeIr 915.2086; found 915.2093 [M-PF6-] + . B.13. Complex (IV-b) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(4- Me-ppy)2IrCl]2 (0.067 g, 0.06 mmol). Yellow solid (0.083 g, 63%). Anal. Calcd. For C46H42F6FeIrN6OP: C, 50.79; H, 3.89; N, 7.73. Found: C, 50.64; H, 3.71; N, 7.65. 1 H NMR (400 MHz, CDCl 3 ): δ 8.86 (d, J = 2.1 Hz, 1H), 8.79 (d, J = 8.3 Hz, 1H), 8.35 (d, J = 1.9 Hz, 1H), 8.21 (t, J = 5.5 Hz, 1H), 8.06-7.99 (m, 1H), 7.89 (d, J = 8.3 Hz, 1H), 7.87-7.79 (m, 2H), 7.76-7.64 (m, 3H), 7.62-7.55 (m, 2H), 7.43 (dd, J = 5.7, 1.5 Hz, 1H), 7.13 (dd, J = 7.4, 5.5 Hz, 1H), 6.99 (ddd, J = 7.4, 5.8, 1.5 Hz, 1H), 6.90 (ddd, J = 7.4, 5.8, 1.4 Hz, 1H), 6.87-6.79 (m, 2H), 6.18-6.13 (m, 1H), 6.07-6.02 (m, 1H), 5.22 (d, J = 1.4 Hz, 1H), 5.16 (d, J = 1.3 Hz, 1H), 4.24 (dd, J = 3.5 Hz, 2H), 4.14 (s, 5H), 3.75 (t, J = 7.0 Hz, 2H), 3.14-2.92 (m, 2H), 2.12 (s, 3H), 2.09 (s, 3H), 1.62-1.43 (m, 2H). 13 C NMR (101 MHz, CDCl 3 ): δ 178.4 (1C), 170.9 (1C), 168.9 (1C), 167.8 (1C), 164.0 (1C), 153.9 (1C), 152.9 (1C), 149.6 (1C), 148.8 (1C), 148.3 (1C), 141.6 (1C), 141.3 (1C), 140.9 (1C), 140.8 (1C), 139.8 (1C), 137.6 (1C), 136.8 (1C), 132.0 (1C), 131.6 (1C l ), 125.6 (1C), 124.8 (1C), 124.6 (1C), 124.1 (1C), 123.4 (1C), 123.4 (1C), 123.1 (1C), 122.0 (1C), 119.4 (1C), 119.3 (1C), 118.5 (1C), 113.8 (1C), 76.4 (1C), 70.3 (1C), 70.2 (1C), 69.7 (5C), 69.1 (1C), 69.1 (1C), 47.8 (1C), 36.1 (1C), 32.1 (1C), 21.9 (2C). HRMS (ES + ): calcd. for C 46 H 42 N 6 OFeIr 943.2402; found 943.2379 [M-PF 6 - ] + . B.14. Complex (IV-c) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(4- COOMe-ppy) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.081 g, 57%). Anal. Calcd. For C48H42F6FeIrN6O5P: C, 49.03; H, 3.60; N, 7.15. Found: C, 49.21; H, 3.53; N, 7.22. 1 H NMR (400 MHz, CDCl3): δ 8.14-8.06 (m, 2H), 8.03 (d, J = 2.3 Hz, 1H), 8.00-7.95 (m, 3H), 7.90-7.80 (m, 3H), 7.75-7.70 (m, 3H), 7.66 (dd, J = 8.2, 1.7 Hz, 1H), 7.62 (dd, J = 5.6, 1.2 Hz, 1H), 7.33 (d, J = 2.2 Hz, 1H), 7.23-7.12 (m, 3H), 7.04 (d, J = 1.6 Hz, 1H), 6.87 (d, J = 1.6 Hz, 1H), 6.20 (t, J = 6.1 Hz, 1H), 4.72 ( d, J = 4.1 Hz, 2H), 4.32 (dd, J = 1.9 Hz, 2H), 4.19-4.15 (m, 5H), 3.78 (s, 3H), 3.77 (s, 3H), 3.55-3.39 (m, 2H), 3.04-2.92 (m, 1H), 2.64-2.55 (m, 1H), 1.60-1.50 (m, 2H). 13 C NMR (101 MHz, CDCl3): δ 177.8 (1C), 170.7 (1C), 167.4 (1C), 167.3 (1C), 167.3 (1C), 165.9 (1C), 162.2 (1C), 153.5 (1C), 153.4 (1C), 149.8 (1C), 149.3 (1C), 148.8 (1C), 147.2 (1C), 147.1 (1C), 141.8 (1C), 138.4 (1C), 137.8 (1C), 131.8 (1C), 131.4 (1C), 131.2 (1C), 130.8 (1C), 125.6 (1C), 124.8 (1C), 124.7 (1C), 124.5 (1C), 124.3 (1C), 124.3 (1C), 124.0 (1C), 123.2 (1C), 121.1 (2C), 118.1 (1C), 113.0 (1C), 75.7 (1C), 70.5 (2C), 69.8 (5C), 68.4 (1C), 68.1 (1C), 52.2 (1C), 52.0 (1C), 48.1 (1C), 36.1 (1C), 32.0 (1C). HRMS (ES + ): calcd. for C 48 H 42 N 6 O 5 FeIr 1031.2195; found 1031.2220 [M-PF 6 -] + . B.14. Complex (IV-d) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(3- COOMe-ppy) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.045 g, 32%). Anal. Calcd. For C 48 H 42 F 6 FeIrN 6 O 5 P: C, 49.03; H, 3.60; N, 7.15. Found: C, 49.17; H, 3.42; N, 7.28. 1 H NMR (400 MHz, CDCl 3 ): δ 8.39 (d, J = 1.8 Hz, 1H), 8.35 (d, J = 1.7 Hz, 1H), 8.17- 7.92 (m, 6H), 7.85 (dd, J = 7.9 Hz, 2H), 7.66 (d, J = 5.6 Hz, 1H), 7.59 (dd, J = 7.8, 1.6 Hz, 1H), 7.54 (d, J = 5.6 Hz, 1H), 7.49 (dd, J = 8.1, 1.7 Hz 1H), 7.35 (d, J = 2.2 Hz, 1H), 7.26-7.15 (m, 2H), 7.11 (dd, J = 6.3 Hz, 1H), 6.48 (d, J = 7.9 Hz, 1H), 6.29 (d, J = 7.8 Hz, 1H), 6.14 (t, J = 6.0 Hz, 1H), 4.78 (s, 2H), 4.38 (s, 2H), 4.24 (s, 5H), 3.88 (s, 3H), 3.86 (s, 3H), 3.51 (t, J = 6.9 Hz, 2H) 2.92-2.85 (m, 2H), 1.59-1.37 (m, 2H). 13 C NMR (101 MHz, CDCl 3 ): δ 177.8 (1C), 171.0 (1C), 170.8 (1C), 167.5 (1C), 167.5 (1C), 167.4 (1C), 166.3 (1C), 157.2 (1C), 153.6 (1C), 153.2 (1C), 149.6 (1C), 149.0 (1C), 144.8 (1C), 143.1 (1C), 142.0 (1C), 138.6 (1C), 137.9 (1C), 131.4 (1C), 131.2 (1C), 131.1 (1C), 130.9 (1C), 125.6 (1C), 125.6 (1C), 125.4 (1C), 125.3 (1C), 124.4 (1C), 124.1 (2C), 123.9 (1C), 120.4 (1C), 120.3 (1C), 118.0 (1C), 113.1 (1C), 76.1 (1C), 71.3 (2C), 70.4 (5C), 68.9 (2C), 52.0 (1C), 52.0 (1C), 48.1 (1C), 36.2 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C48H42N6O5FeIr 1031.2195; found 1031.2218 [M-PF6-] + . B.15. Complex (IV-e) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(p- 3-COOMe-ppy)2IrCl]2 (0.078 g, 0.06 mmol). Yellow solid (0.056 g, 40%). Anal. Calcd. For C48H42F6FeIrN6O5P: C, 49.03; H, 3.60; N, 7.15. Found: C, 49.22; H, 3.64; N, 7.27. 1 H NMR (400 MHz, CDCl3): δ 9.02 (d, J = 2.3 Hz, 1H), 8.96 (d, J = 8.4 Hz, 1H), 8.49 (d, J = 2.2 Hz, 1H), 8.46 (d, J = 1.9 Hz, 1H), 8.34-8.26 (m, 2H,), 8.20 (t, J = 5.6 Hz, 1H), 8.14 (ddd, J = 8.7, 7.6, 1.7 Hz, 1H), 8.04 (d, J = 2.0 Hz, 1H), 8.01 (d, J = 8.7 Hz, 1H), 7.97 (d, J = 8.6 Hz, 1H), 7.80-7.74 (m, 2H), 7.71 (dd, J = 5.5, 1.8 Hz, 1H), 7.26-7.15 (m, 1H), 7.14-6.99 (m, 3H), 6.97-6.91 (m, 1H), 6.38 (dd, J = 7.8, 1.1 Hz, 1H), 6.26 (dd, J = 7.5, 1.3 Hz, 1H), 5.22-5.07 (m, 2H), 4.21 (dd, J = 2.0 Hz, 2H), 4.13 (s, 5H), 3.93-3.78 (m, 7H), 3.56-3.46 (m, 1H), 3.15-3.06 (m, 2H), 1.77-1.65 (m, 2H). 13 C NMR (101 MHz, CDCl 3 ): δ 176.7 (1C), 172.5 (1C), 171.1 (1C), 171.0 (1C), 165.1 (1C), 163.6 (1C), 163.2 (1C), 154.5 (1C), 153.9 (1C), 150.4 (1C), 149.9 (1C), 149.6 (1C), 143.0 (1C), 142.0 (1C), 141.1 (1C), 138.7 (1C), 137.8 (1C), 132.3 (1C), 132.0 (1C), 131.4 (1C), 131.1 (1C), 126.5 (1C), 126.3 (1C), 126.0 (1C), 126.0 (1C), 124.7 (1C), 123.8 (1C), 123.5 (1C), 122.5 (1C), 119.3 (1C), 119.1 (2C), 114.5 (1C), 76.3 (1C), 70.2 (1C), 70.2 (1C), 69.6 (5C), 69.2 (1C), 69.0 (1C), 53.1 (1C), 52.8 (1C), 47.7 (1C), 36.0 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C 48 H 42 N 6 O 5 FeIr 1031.2195; found 1031.2192 [M-PF 6 -] + . B.16. Complex (IV-f) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(p- 3-COOH-ppy) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.052 g, 37%). Anal. Calcd. For C 46 H 38 F 6 FeIrN 6 O 5 P: C, 48.13; H, 3.34; N, 7.32. Found: C, 48.33; H, 3.28; N, 7.25. 1 H NMR (400 MHz, MeOD): δ 8.65 (d, J = 1.8 Hz, 1H), 8.37 (dd, J = 8.4, 1.8 Hz, 1H), 8.32 (dd, J = 8.4, 1.8 Hz, 1H), 8.27 (d, J = 2.2 Hz, 1H), 8.23 (d, J = 1.8 Hz, 1H), 8.20- 8.06 (m, 4H), 7.88-7.82 (m, 2H), 7.81 (dd, J = 5.6, 1.6 Hz, 1H), 7.44 (d, J = 2.2 Hz, 1H), 7.28 (ddd, J = 7.1, 5.6, 1.3 Hz, 1H), 7.03 (ddd, J = 7.2, 5.3, 1.3 Hz, 1H), 6.99- 6.90 (m, 2H), 6.77 (ddd, J = 7.2, 5.3, 1.3 Hz, 1H), 6.42 (dd, J = 7.7, 1.2 Hz, 1H), 6.27 (dd, J = 7.4, 1.3 Hz, 1H), 4.96-4.90 (m, 1H), 4.81-4.72 (m, 1H), 4.42-4.36 (m, 2H), 4.13 (s, 5H), 3.71-3.58 (m, 1H), 3.53-3.43 (m, 1H), 3.23-3.10 (m, 1H), 2.96-2.85 (m, 1H), 1.81-1.56 (m, 2H). 13 C NMR (101 MHz, MeOD): δ 178.9 (1C), 172.1 (1C), 169.9 (1C), 169.1 (1C), 168.8 (1C), 168.4 (1C), 164.1 (1C), 154.8 (1C), 153.7 (1C), 150.2 (1C), 149.6 (1C), 149.6 (1C), 144.1 (1C), 142.5 (1C), 141.1 (1C), 138.5 (1C), 137.7 (1C), 133.4 (1C), 132.5 (1C), 131.0 (1C), 130.9 (1C), 130.5 (1C), 129.9 (1C), 125.1 (1C), 125.0 (1C), 124.0 (1C), 123.7 (1C), 122.7 (1C), 121.2 (1C), 118.8 (1C), 118.4 (1C), 117.6 (1C), 112.6 (1C), 74.9 (1C), 70.6 (1C), 70.3 (1C), 69.4 (5C), 68.3 (1C), 68.1 (1C), 47.5 (1C), 36.3 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C46H38N6O5FeIr 1003.1882; found 1003.1898 [M-PF6-] + . B.17. Complex (IV-g) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(pq) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.070 g, 50%). Anal. Calcd. For C 52 H 42 F 6 FeIrN 6 OP: C, 53.84; H, 3.65; N, 7.25. Found: C, 53.77; H, 3.89; N, 7.14. 1 H NMR (400 MHz, CDCl 3 ): δ 8.37 (d, J = 2.1 Hz, 1H), 8.33-8.20 (m, 4H), 8.17 (d, J = 2.1 Hz, 1H), 8.12 (d, J = 8.7 Hz, 1H), 8.09-8.00 (m, 2H), 7.94-7.87 (m, 1H), 7.87- 7.80 (m, 1H), 7.79-7.70 (m, 2H), 7.67-7.60 (m, 2H), 7.38-7.22 (m, 3H), 7.13-7.01 (m, 4H), 6.92 (ddd, J = 8.7, 6.8, 1.5 Hz, 1H), 6.83 (ddd, J = 8.5, 6.4, 1.2 Hz, 1H), 6.72 (ddd, J = 8.4, 6.5, 1.3 Hz, 1H), 6.58 (dd, J = 7.9, 1.2 Hz, 1H), 6.28 (dd, J = 7.6, 1.2 Hz, 1H), 5.24-5.15 (m, 2H), 4.25-4.19 (m, 2H), 4.14 (s, 5H), 3.86-3.71 (m, 1H), 3.62- 3.48 (m, 1H), 3.1-3.00 (m, 2H), 1.81-1.66 (m, 1H), 1.5-1.40 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 178.5 (1C), 171.2 (1C), 170.9 (1C), 170.7 (1C), 164.5 (1C), 152.9 (1C), 149.5 (1C), 148.3 (1C), 147.1 (1C), 146.7 (1C), 146.7 (1C), 144.4 (1C), 141.1 (1C), 139.8 (1C), 139.2 (1C), 133.2 (1C), 132.6 (1C), 131.5 (1C), 131.1 (1C), 131.1 (1C), 130.9 (1C), 129.1 (1C), 128.9 (1C), 127.6 (1C), 127.5 (1C), 127.2 (1C), 126.9 (1C), 126.7 (1C), 126.6 (1C), 126.5 (1C), 125.2 (1C), 124.7 (1C), 123.3 (1C), 122.8 (1C), 122.1 (1C), 118.1 (1C), 117.7 (1C), 117.5 (1C), 113.5 (1C), 76.4 (1C), 70.2 (1C), 70.2 (1C), 69.6 (5C), 69.2 (1C), 69.0 (1C), 47.1 (1C), 36.3 (1C), 30.6 (1C). HRMS (ES + ): calcd. for C52H42N6OFeIr 1015.2404; found 1015.2403 [M-PF6-] + . B.18. Complex (IV-h) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(piq)2IrCl]2 (0.078 g, 0.06 mmol) in MeCN (10 mL). Yellow solid (0.048 g, 35%). Anal. Calcd. For C52H42F6FeIrN6OP: C, 53.84; H, 3.65; N, 7.25. Found: C, 53.77; H, 3.89; N, 7.14. 1 H NMR (400 MHz, MeOD): δ 9.08-9.01 (m, 1H), 8.99-8.92 (m, 1H), 8.43 (d, J = 8.1 Hz, 1H), 8.37 (d, J = 2.2 Hz, 1H), 8.29 (d, J = 7.9 Hz, 1H), 8.24 (d, J = 8.4 Hz, 1H), 8.22-8.11 (m, 1H), 8.05-7.97 (m, 2H), 7.88-7.80 (m, 5H), 7.62 (dd, J = 5.6, 1.6 Hz, 1H), 7.58-7.50 (m, 3H), 7.46 (d, J = 6.5 Hz, 1H), 7.33-7.25 (m, 1H), 7.25- 7.07 (m, 2H), 6.95 (ddd, J = 8.3, 6.3, 1.1 Hz, 1H), 6.88-6.80 (ddd, J = 8.4, 6.3, 1.1 Hz, 1H), 6.41 (dd, J = 7.7, 1.2 Hz, 1H), 6.25 (dd, J = 7.5, 1.3 Hz, 1H), 4.71 (dd, J = 1.9 Hz, 2H), 4.38 (dd, J = 2.0 Hz, 2H), 4.08 (s, 5H), 3.67-3.41 (m, 2H), 2.95-2.72 (m, 2H), 1.60-1.39 (m, 2H). 13 C NMR (101 MHz, MeOD): δ 180.0 (1C), 171.9 (1C), 170.2 (1C), 167.9 (1C), 165.6 (1C), 153.5 (1C), 152.5 (1C), 149.4 (1C), 146.0 (1C), 144.7 (1C), 144.4 (1C), 141.4 (1C), 140.8 (1C), 136.9 (1C), 136.6 (1C), 131.7 (1C), 131.4 (1C), 131.3 (1C), 131.1 (1C), 130.7 (1C), 130.5 (1C), 130.4 (1C), 129.9 (1C), 128.7 (1C), 128.6 (1C), 127.4 (1C), 127.2 (1C), 126.9 (1C), 126.4 (1C), 126.4 (1C), 126.3 (1C), 123.8 (1C), 123.8 (1C), 122.5 (1C), 122.2 (1C), 121.2 (1C), 121.0 (1C), 117.8 (1C), 112.5 (1C), 75.0 (1C), 70.4 (1C), 70.4 (1C), 69.4 (5C), 68.0 (1C), 67.9 (1C), 47.2 (1C), 36.1 (1C), 31.8 (1C). HRMS (ES + ): calcd. for C 52 H 42 N 6 OFeIr 1015.2404; found 1015.2426 [M-PF 6 -] + . B.19. Complex (IV-i) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(bzq) 2 IrCl] 2 (0.078 g, 0.06 mmol) in MeCN (10 mL). Yellow solid (0.041 g, 31%). Anal. Calcd. For C 48 H 38 F 6 FeIrN 6 OP: C, 52.04; H, 3.46; N, 7.59. Found: C, 52.18; H, 3.34; N, 7.72. 1 H NMR (400 MHz, CDCl 3 ): δ 8.96 (s, 1H), 8.88 (d, J = 8.2 Hz, 1H), 8.35-8.29 (m, 1H), 8.29-8.21 (m, 3H), 8.02 (t, J = 5.3 Hz, 1H), 7.99-7.93 (m, 1H), 7.86-7.79 (m, 3H), 7.72-7.59 (m, 3H), 7.50-7.41 (m, 3H), 7.37 (dd, J = 8.0, 5.4 Hz, 1H), 7.19 (dd, J = 7.4 Hz, 1H), 7.10 (dd, J = 7.6 Hz, 1H), 6.99 (dd, J = 6.5 Hz, 1H), 6.38-6.28 (m, 2H), 5.18-5.09 (m, 2H), 4.23-4.17 (m, 2H), 4.10 (s, 5H), 3.59 (t, J = 7.0 Hz, 2H), 2.8-2.64 (m, 2H), 1.33-120 (m, 1H), 0.92-0.79 (m, 1H). 13 C NMR (101 MHz, CDCl3): δ 177.1 (1C), 170.8 (1C), 161.1 (1C), 158.4 (1C), 157.2 (1C), 154.2 (1C), 152.0 (1C), 150.0 (1C), 147.1 (1C), 145.0 (1C), 141.5 (1C), 141.2 (1C), 139.9 (1C), 136.9 (1C), 136.1 (1C), 134.4 (1C), 134.3 (1C), 130.4 (1C), 130.3 (1C), 130.1 (1C), 129.8 (1C), 128.9 (1C), 128.3 (1C), 127.4 (1C), 127.1 (1C), 125.5 (1C), 123.6 (1C), 123.4 (1C), 123.4 (1C), 122.8 (1C), 121.5 (1C), 121.0 (1C), 119.8 (1C), 118.7 (1C), 114.0 (1C), 76.3 (1C), 70.2 (2C), 69.6 (5C), 69.1 (2C), 47.8 (1C), 35.9 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C48H38N6OFeIr 963.2086; found 963.2069 [M-PF6-] + . B.20. Complex (IV-j) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(thpy) 2 IrCl] 2 (0.078 g, 0.06 mmol) in MeCN (10 mL). Yellow solid (0.056 g, 40%). Anal. Calcd. For C 48 H 38 F 6 FeIrN 6 OPS 2 : C, 49.19; H, 3.27; N, 7.17. Found: C, 49.34; H, 3.18; N, 7.09. 1 H NMR (400 MHz, CDCl 3 ): δ 9.24 (d, J = 2.2 Hz, 1H), 9.12 (d, J = 8.4 Hz, 1H), 8.38 (d, J = 2.1 Hz, 1H), 8.03 (t, J = 7.1 Hz, 1H), 7.85-7.72 (m, 6H), 7.72- 7.64 (m, 2H), 7.61 (d, J = 8.0 Hz, 1H), 7.51 (d, J = 5.9 Hz, 1H), 7.21-7.13 (m, 2H), 7.09 (ddd, J = 7.4, 5.8 Hz, 1H), 6.97 (ddd, J = 7.4, 5.8, 1.5 Hz, 1H), 6.90-6.79 (m, 3H), 6.08 (d, J = 8.2 Hz, 1H), 5.95 (d, J = 8.1 Hz, 1H), 5.12-5.07 (m, 1H), 5.06-5.01 (m, 1H), 4.23-.17 (m, 2H), 4.08 (s, 5H), 3.74-3.55 (m, 2H), 2.84-2.61 (m, 2H), 1.69- 1.54 (m, 1H), 1.32-1.20 (m, 1H). 13 C NMR (101 MHz, CDCl 3 ): δ 173.5 (1C), 171.7 (1C), 165.5 (1C), 164.5 (1C), 162.2 (1C), 153.4 (1C), 153.2 (1C), 150.7 (1C), 149.3 (1C), 146.4 (1C), 146.0 (1C), 145.4 (1C), 143.6 (1C), 142.3 (1C), 139.4 (1C), 138.7 (1C), 138.5 (1C), 134.1 (1C), 125.8 (1C), 125.6 (1C), 125.0 (3C), 124.7 (1C), 124.5 (1C), 124.3 (1C), 124.2 (1C), 123.3 (1C), 123.0 (1C), 121.9 (1C), 120.3 (1C), 120.0 (1C), 119.5 (1C), 118.3 (1C), 113.0 (1C), 74.9 (1C), 70.6 (2C), 69.6 (5C), 68.1 (1C), 68.0 (1C), 48.0 (1C), 36.1 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C 48 H 38 N 6 OS 2 FeIr 1027.1527; found 1027.1531 [M-PF 6 -] + . B.21. Complex (IV-k) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(pbt)2IrCl]2 (0.078 g, 0.06 mmol) in MeCN (10 mL). Yellow solid (0.092 g, 66%). Anal. Calcd. For C48H38F6FeIrN6OPS2: C, 49.19; H, 3.27; N, 7.17. Found: C, 49.32; H, 3.14; N, 7.11. 1 H NMR (400 MHz, CDCl3): δ 8.99 (s, 1H), 8.95-8.84 (m, 1H), 8.69 (s, 1H), 8.22-8.12 (m, 1H), 8.11-8.00 (m, 1H), 7.94-7.69 (m, 5H), 7.40-7.32 (m, 2H), 7.29-7.26 (m, 1H), 7.16 (dd, J = 6.4, 6.3 Hz, 1H), 7.12-7.01 (m, 3H), 6.94 (t, J = 7.4 Hz, 1H), 6.82 (t, J = 7.5 Hz, 1H), 6.41-6.35 (m, 3H), 6.05 (d, J = 8.3 Hz, 1H), 5.25- 5.13 (m, 2H), 4.26-4.18 (m, 2H), 4.12 (s, 5H), 3.90-3.75 (m, 1H), 3.72-3.58 (m, 1H), 3.09-2.95 (m, 2H), 1.97-1.75 (m, 2H). 13 C NMR (101 MHz, CDCl3): δ 182.6 (1C), 179.8 (1C), 174.5 (1C), 171.0 (1C), 164.2 (1C), 154.4 (1C), 150.0 (1C), 149.8 (1C), 149.1 (1C), 148.9 (1C), 141.8 (1C), 140.7 (1C), 138.9 (1C), 132.7 (1C), 132.5 (1C), 132.3 (1C), 132.1 (1C), 131.3 (1C), 131.0 (1C), 128.6 (1C), 127.9 (1C), 126.7 (1C), 126.3 (2C), 126.1 (1C), 125.8 (1C), 123.6 (1C), 123.5 (1C), 123.3 (1C), 123.3 (1C), 122.7 (1C), 118.6 (1C), 118.6 (1C), 117.5 (1C), 113.9 (1C), 76.3 (1C), 70.2 (2C), 69.6 (5C), 69.2 (1C), 69.1 (1C), 47.8 (1C), 36.2 (1C), 31.1 (1C). HRMS (ES + ): calcd. for C 48 H 38 N 6 OS 2 FeIr 1027.1527; found 1027.1517 [M-PF 6 -] + . B.22. Complex (IV-l) From (IV) (0.06 g, 0.12 mmol), silver oxide (0.028 g, 0.12 mmol) and [(2,4-F-ppy) 2 IrCl] 2 (0.078 g, 0.06 mmol). Yellow solid (0.076 g, 56%). Anal. Calcd. For C 44 H 34 F 10 FeIrN 6 OP: C, 46.69; H, 3.03; N, 7.43. Found: C, 46.54; H, 3.25; N, 7.32. 1 H NMR (400 MHz, MeOD): δ 8.50-8.31 (m, 3H), 8.31-8.18 (m, 2H), 8.11-8.03 (m, 1H), 8.02-7.92 (m, 2H), 7.85-7.79 (m, 1H), 7.77-7.70 (m, 1H), 7.62 (d, J = 2.3 Hz, 1H), 7.45-7.40 (m, 1H), 7.27-7.11 (m, 2H), 6.73-6.61 (m, 2H), 5.83 (dd, J = 8.7, 2.5 Hz, 1H), 5.65 (dd, J = 8.0, 2.4 Hz, 1H), 4.80-4.71 (m, 2H), 4.42 (dd, J = 2.0 Hz, 2H), 4.17 (s, 5H), 3.85-3.57 (m, 2H), 3.10-2.81 (m, 2H), 1.64-1.51 (m, 2H). 13 C NMR (101 MHz, MeOD): δ 176.4 (1C), 172.0 (1C), 168.0 (1C), 164.7 (d, J = 7.0 Hz, 1C), 164.4 (dd, J = 257, 12 Hz, 1C), 163.5 (dd, J = 236, 13 Hz, 1C), 162.2 (d, J = 7 Hz, 1C), 161.6 (dd, J = 240, 11 Hz, 1C), 161.8 (dd, J = 260, 13 Hz, 1C), 153.6 (1C), 153.4 (1C), 153.0 (d, J = 7 Hz, 1C), 149.6 (1C), 149.5 (1C), 142.1 (1C), 139.1 (1C), 138.5 (1C), 127.9 (1C), 127.1 (1C), 124.5 (1C), 124.4 (1C), 124.2 (1C), 123.8 (1C), 123.5 (1C), 123.3 (1C), 118.2 (1C), 113.0 (1C), 112.7 (dd, J = 25, 3 Hz, 1C), 112.6 (dd, J = 25, 3 Hz, 1C), 99.0 (t, J = 27 Hz, 1C), 97.6 (t, J = 27 Hz, 1C), 75.1 (1C), 70.5 (2C), 69.5 (5C), 68.2 (1C), 68.1 (1C), 47.8 (1C), 36.1 (1C), 31.7 (1C). HRMS (ES + ): calcd. for C44H34N6OF4FeIr 987.1709; found 987.1716 [M-PF6-] + . II. Properties of the complexes according to the invention. II.1. Lipophilicity of vectorized iridium(III) complexes. A. Lipophilicity measurement. The octanol-water partition coefficients (P) of all the complexes were determined using a shake-flask method 8 . Water (100 mL, distilled after milli-Q purification) and n-octanol (100 mL, Sigma Aldrich, ACS spectrophotometric grade, ≥ 99%) were shaken together for 24 h to allow saturation of both phases. Stock solutions of the compounds (50 µM) were prepared in the aqueous phase. Aliquots (2 mL) of each of these stock solutions were then added to an equal volume of the n-octanol phase. The resultant biphasic solution was mixed for 15 min and then centrifuged (3000 tr/min, 5 min) to separate the phases. The concentrations of the complex in the organic and aqueous phases were then determined using UV absorbance spectroscopy (260 nm). The blank is the water saturated with n-octanol. Log P was defined as logarithm of the ratio of the concentrations of the complex in the organic and aqueous phases (values reported are the means of at least three determinations). ( ^^) B. Result on lipophilicity. The lipophilicity, which refers to the partition coefficient of the compound in n-octanol/water, has been measured for all the vectorized iridium(III) complexes (Table 3). The Log P values have been determined by a classical shake-flask method [8]. The Log P values of iridium(III) complexes range from -0.78 to 1.26 for biotin vectorized iridium(III) complexes, 1.08 to 2.06 for FTS vectorized iridium(III) complexes, -0.52 to 0.88 for PSMA vectorized iridium(III) complexes, and 0.61 to 2.73 for Fc vectorized iridium(III) complexes. In a given family of vectorized iridium(III) complexes, the lipophilicity is mainly regulated by modification of the structures of the C^N ligands. As expected, the complexes containing deprotonated 3- or 4-COOMe substituted phenylpyridine ligands and p-3-COOH substituted phenylpyridine ligand are the most hydrophilic. In contrary, the complexes with extended π-conjugation ligands, in particular containing deprotonated 2-phenylquinoline, 1-phenylisoquinoline and 7,8-benzoquinoline ligands or containing F groups show lipophilic character, the most lipophilic one being (II-l) with a Log P value of 2.06. Table 3 : Lipophilicity of vectorized iridium(III) complexes (I-a) to (I-l), (II-a-e) and (II-g-l), (III-a-b), (III-d-e) and (III-g-l) and (IV-a) and (IV-l). Entry Complex Log P Entry Complex Log P 1 (I-a) 0.09±0.07 24 (III-a) -0.52±0.04 2 (I-b) 0.43±0.01 25 (III-b) -0.14±0.04 3 (I-c) -0.78 ±0.01 26 (III-d) -0.52±0.01 4 (I-d) -0.10±0.01 27 (III-e) -033±0.03 5 (I-e) 0.25±0.04 28 (III-g) 0.33±0.01 6 (I-f) -0.68±0.07 29 (III-h) 0.88±0.02 7 (I-g) 1.26±0.04 30 (III-i) 0.60±0.01 8 (I-h) 0.87±0.02 31 (III-j) -0.38±0.03 9 (I-i) 0.60±0.06 32 (III-k) -0.14±0.01 10 (I-j) 0.24±0.05 33 (III-l) 0.29±0.05 11 (I-k) 0.87±0.03 34 (IV-a) 0.61±0.07 12 (I-l) 0.50±0.02 35 (IV-b) 1.63±0.02 13 (II-a) 1.70±0.08 36 (IV-c) 0.72±0.03 14 (II-b) 1.68 ±0.02 37 (IV-d) 0.77±0.01 15 (II-c) 1.08 ±0.01 38 (IV-e) 1.37±0.05 16 (II-d) 1.40±0.02 39 (IV-f) 1.08±0.03 17 (II-e) 1.30±0.02 40 (IV-g) 1.42±0.06 18 (II-g) 1.95±0.05 41 (IV-h) 0.81±0.07 19 (II-h) 2.06±0.07 42 (IV-i) 0.74±0.02 20 (II-i) 1.82±0.01 43 (IV-j) 1.07±0.07 21 (II-j) 1.94±0.06 44 (IV-k) 0.74±0.05 22 (II-k) 1.60±0.01 45 (IV-l) 1.14±0.02 23 (II-l) 2.06±0.06 II.2. Photophysical properties of vectorized iridium(III) complexes. A. Photophysical mesurement. UV/Vis absorption spectra were recorded at RT on solutions contained in quartz cuvettes (optical pathlength 1 cm, Hellma®) with a PerkinElmer® UV/VIS/NIR spectrophotometer Lambda 950 and a PerkinElmer® detector UV/VIS/NIR Accessory 2D Detector Module. Fluorescence and phosphorescence emission spectra were obtained with a HORIBA JOBIN YVON, fluromax-4 and spectrofluorometer. Luminescence quantum yields were measured according to the method of Demas and Crosby [9], on solution samples at RT. The quantum yield is defined as: ^ Where Φ ^ is the quantum yield of the sample, Φ ^ is the know quantum yield of the reference standard. At the area subtended by the emission band (on a wavelength scale) and η is the refractive index of the solvent used for the preparation of the solution. A s (related to the sample) and A r (related to the reference) must be excitation wavelength. Different standards were selected depending on the spectral region of the interest: POPOP in hexane (Φ = 97%) and rhodamine B in ethanol (Φ = 65%). Fluorescence lifetime measurements were performed by an Edinburgh FLS920 spectrofluorimeter equipped with a TCC900 card for data acquisition in time-correlated single-photon counting experiments (0.5 ns time resolution) with a D2 lamp and an LDH-P-C-405 pulsed diode laser. The estimated experimental error is 2 nm on the band maximum (5% on the lifetime, 10% on the fluorescence quantum yield). B. Result on photophysical properties. The absorption spectra of vectorized iridium(III) complexes were determined in CH2Cl2 or in CH2Cl2/MeOH (1:1) solutions at room temperature (Table 4). All the complexes displayed intense absorption bands below 300 nm, which can be assigned to spin-allowed 1 π→π* (C^N) electronic ligand-centered ( 1 LC) transitions [10-15]. The structureless bands at 300-360 nm were attributed both to phenyl-to-pyridine π−π* (C^N) ligand-to-ligand charge transfer ( 1 LLCT) and metal-to-ligand charge transfer dπ(Ir)→π*(C^N) with a predominant singlet spin multiplicity ( 1 MLCT) 9–14 . The weak and broad lowest-lying bands in the visible region over 360 nm corresponds to both singlet and triplet metal-to-ligand charge transfer dπ(Ir)→π*(C^N) ( 1 MLCT and 3 MLCT) transitions [10-15]. In this area, the complexes bearing C^N ligands such as 2,4-F-ppy (complexes (I-l), (II-l), (III-l), (IV- l)) show maximum absorption ranging from 356-361 nm, 3-COOMe-ppy (complexes (I-d), (II-d), (III-d), (IV-d)) show maximum absorption around 370 nm, and ppy (complexes ((I-a), (II-a), (III-a), (IV-a)) and 4-Me-ppy (complexes (I-b), (II- b), (III-b), (IV-b)) show maximum absorption around 380 nm. the complexes bearing C^N ligands such as 4-COOMe-ppy (complexes (I-c), (II-c), (III-c), (IV-c)), bzq (complexes (I-i), (II-i), (III-i), (IV-i)) and pbt (complexes (I-k), (II-k), (III-k), (IV- k)) show maximum absorption ranging from 398-413 nm. The complexes with C^N ligands such as p-3-COOMe-ppy (complexes (I-e), (II-e), (III-e), (IV-e)), pq (complexes (I-g), (II-g), (III-g), (IV-g)), piq (complexes (I-h), (II-h), (III-h), (IV-h)), and thpy (complexes (I-j), (II-j), (III-j), (IV-j)) exhibit a maximum ranging from 428- 438 nm absorption in the visible region corresponding to the blue area. The relatively weak ferrocene-based bands that generally appear around 450 nm and correspond to spin allowed d-d transitions are masked by the MLCT ones. Table 4 : Selected UV-visible properties of vectorized iridium(III) complexes (I-a-e) to (I-g-l), (II-a-e) and (II-g-l), (III-a-b), (III-d- l) and (IV-a) and (IV-l). Entry Complex ε (M -1 .cm -1 ) 1 (I-a) 308 (sh) (16690), 380 (5560) 2 (I-b) 314 (sh) (18240), 382 (6150) 3 (I-c) 310 (sh) (16860), 358 (4090), 400 (3295) 4 (I-d) 373 (4260) 5 (I-e) 310 (sh) (19500), 365 (sh) (4690), 432 (4155) 6 (I-g) 336 (19000), 437 (4600) 7 (I-h) 337 (sh) (12520), 352 (sh) (11890), 380 (sh) (8100), 436 (4855) 8 (I-i) 320 (13840), 410 (3920) 9 (I-j) 324 (sh) (15070), 342 (sh) (13570), 430 (5960) 10 (I-k) 321 (25835), 372 (sh) (7480), 406 (6130) 11 (I-l) 300 (sh) (14510), 359 (4820) 12 (II-a) 308 (sh) (14540), 380 (4505) 13 (II-b) 306 (sh) (15875), 382 (4560) 14 (II-c) 310 (sh) (21710), 355 (5105), 398 (3925) 15 (II-d) 372 (4535) 16 (II-e) 310 (sh) (24540), 363 (sh) (5975), 432 (5280) 17 (II-g) 333 (20560), 438 (4735) 18 (II-h) 332 (sh) (12380), 353 (sh) (11525), 380 (sh) (8040), 436 (4810) 19 (II-i) 315 (16900), 412 (4615) 20 (II-j) 324 (16000), 341 (sh) (14300), 430 (6205) 21 (II-k) 321 (32250), 372 (sh) (9520), 406 (7855) 22 (II-l) 300 (sh) (21325), 361 (6610) 24 (III-a) 303 (sh) (37760), 380 (14610), 462 (sh) (570) 25 (III-b) 310 (sh) (23310), 379 (7615) 26 (III-d) 370 (13650), 452 (sh) (565) 27 (III-e) 308 (sh) (35630), 363 (sh) (8950), 429 (8065) 28 (III-g) 334 (18100), 436 (4280) 29 (III-h) 336 (sh) (23695), 352 (sh) (22270), 378 (sh) (15520), 435 (9310) 30 (III-i) 317 (19830), 412 (5510) 31 (III-j) 324 (26900), 343 (sh) b (24560), 428 (10800) 32 (III-k) 321 (39070), 370 (sh) (12560), 406 (10170) 33 (III-l) 300 (sh) (17230), 360 (5740) 34 (IV-a) 304 (sh) (25840), 381 (8080) 35 (IV-b) 308 (sh) (27820), 379 (8620) 36 (IV-c) 304 (sh) (28570), 353 (sh) (7050), 399 (5315), 427 (sh) (3660) 37 (IV-d) 335 (sh) (9725), 372 (6540) 38 (IV-e) 312 (sh) (27925), 363 (sh) (7290), 434 (6530) 39 (IV-f) 304 (sh) (22560), 410 (4150) 40 (IV-g) 334 (17135), 436 (4150) 41 (IV-h) 334 (sh) (19440), 351 (sh) (18355), 380 (12745), 435 (7870) 42 (IV-i) 318 (25600), 413 (7410) 43 (IV-j) 322 (15400), 342 (sh) (14040), 434 (6150) 44 (IV-k) 321 (24910), 371 (sh) (7200), 407 (5940) 45 (IV-l) 305 (sh) (21345), 356 (sh) (8645), 412 (3395) a UV-Visible spectra were recorded at room temperature in air-saturated CH2Cl2 solutions (50 µM) for complexes (I-a-e) and (I-g-l), (II-a-e) and (II-g-l) and (IV-a-e) and (IV-g-l), and in CH 2 Cl 2 /MeOH (1:1) solutions (50 µM) for complexes (III-a-b), (III-d-e) and (III-g-l) and (IV-f). b (sh) for shoulder. The luminescence spectra of vectorized iridium(III) complexes were determined in CH2Cl2 at room temperature (Table 3). When excited at 365 nm, biotin- or FTS-vectorized iridium complexes (I-a), (II-a), (I-b), (II-b), (I-d), (II-d and (I-l), (II-l) exhibit blue-green phosphorescent emission with two maximum wavelengths ranging from 452-475 nm to 478-505 nm; biotin- or FTS-vectorized iridium complexes (II-e), (I-c), (II-c), (II-i) and (I-k), (II-k) display green to orange phosphorescent emission with two maximum wavelengths from 500-524 nm to 534-558 nm, except complexes (I-e) and (I-i) which show a broad band from 511 to 550 nm and from 522 to 567 nm, respectively. When excited at 470 nm, biotin- or FTS-vectorized iridium complexes (II-h) and (I-j), (II-j) display orange to red phosphorescent emission with two maximum wavelengths ranging from 586- 593 nm to 626-633 nm and complexes (I-g), (II-g), (I-h) show a broad band from 593 to 652 nm and from 554 to 637 nm, respectively. When excited at 365 nm, PSMA-vectorized iridium complex (III-l) displays blue phosphorescent emission with two maximum wavelengths at 453 to 479 nm, PSMA-vectorized complexes (III-b) and (III-d) exhibit blue-green phosphorescent emission with three maximum wavelengths ranging from 476 to 546 nm for (III-b) and one maximum wavelength at 498 nm for (III-d), PSMA- vectorized complexes (III-a) and (III-e) display green phosphorescent emission with one maximum wavelength ranging from 528 to 542 nm, and PSMA- vectorized complex (III-k) display green phosphorescent emission with two maximum wavelengths at 520 to 558 nm. When excited at 470 nm, PSMA- vectorized complex (III-i) displays green-yellow phosphorescent emission with one maximum wavelength at 548 nm, PSMA-vectorized complex (III-j) displays yellow-orange phosphorescent emission with two maximum wavelengths at 584 to 635 nm, and PSMA-vectorized complexes (III-g) and (III-h) exhibit orange phosphorescent emission with one maximum wavelength at 593 and 628 nm, respectively. When excited at 365 nm, Fc-vectorized iridium complexes (IV-a), (IV-b), (IV-d), and (IV-l) exhibit blue-green phosphorescence emission with two maximum wavelengths ranging from 461-475 nm to 490-536 nm for (IV-a), (I-Vb), and (IV-d) and four maximum wavelengths at 452, 477, 515 and 547 nm for (IV-l), whereas Fc-vectorized iridium complexes (IV-c), (IV-e), (IV-f), (IV-k) display green phosphorescent emissions with two maximum wavelengths ranging from 445- 518 nm to 536-558 nm for (IV-c), (IV-f), (IV-k) and with one maximum wavelength at 528 nm for complex (IV-e). When excited at 470 nm, Fc-vectorized complexes (IV-g), (IV-h), (IV-i), and (IV-j) show orange phosphorescent emission with two maximum wavelengths ranging from 574-615 nm to 626-668 nm for complexes (IV-h), (IV-i), and (IV-j) and one maximum wavelength at 579 nm for complex (IV- g). In addition, the relative emission quantum yields (Φ P ) of iridium complexes (I-a-e), (I-i), (I-k), (II-a-e), (II-i), (II-k), (II-l), (III-a-b), (III-d-e), (III-k-l) and (IV-a) to (IV-l) were measured at room temperature by using 1,4-bis(5- phenyloxazole-2-yl)benzene (POPOP) in hexane as a reference standard (Φ P = 97%), and those of complexes (I-g-h), (I-j), (II-g-h), (II-j), (III-g-j) were measured by using rhodamine B in ethanol as a reference standard (Φ P = 65%). The quantum yields of biotin vectorized complexes (I-a-b), (I-d), (I-g), (I-i-j), (I-l) are low (below 1%); for the biotin vectorized complexes (I-c), (I-e), (I-h), (I-k), they are higher with values of 5.9, 3.7, 3.0, and 7.0% respectively (Table 5). The quantum yields of FTS-vectorized complexes (II-a-b), (II-d), (II-g), (II-j), (II-l) are below 1%; for the FTS-vectorized complexes (II-c), (II-e), (II-h), (II-k) they are higher with values of 4.6, 4.6, 3.0, and 6.1%, respectively (Table 2). The quantum yields of PSMA- vectorized complexes (III-g) and (III-i) were below 1%, while PSMA-vectorized complexes (III-a), (III-e), (III-h), (III-j), and (III-k) gave values as high as 9.6, 4.0, 3.0, 3.0, and 6.1%, respectively (Table 5). The quantum yields of all the Fc- vectorized complexes (IV-a) to (IV-l) are below 1% (Table 5). The emission lifetime of all iridium complexes, which refer to the average time that the compound stays in its excited state before emitting a photon, are showed in Table 4. The emission lifetimes of biotin-vectorized complexes (I-a) to (I-l) range from 138 ns to 411 ns, among them, the lifetime of biotin-vectorized complexes (I-c), (I-e), (I-k) are 411, 224, and 322 ns respectively. The emission lifetimes of FTS-vectorized complexes (II-a) to (II-l) range from 167 ns to 486 ns, among them, the lifetime of FTS-vectorized complexes (II-c) and (II-k) are 319 and 486 ns respectively. The emission lifetimes of PSMA-vectorized complexes (III-a) to (III-l) are in the range of 159-649 ns, among them, the lifetime of complexes (III-a) and (III-k) were 248 and 649 ns, respectively. The emission lifetimes of Fc-vectorized complexes (IV-a) to (IV-l) are in the range of 178-228 ns. Table 5 : Photophysical properties of vectorized iridium(III) complexes (I-a-e) to (I- g-l), (II-a-e) and (II-g-l), (III-a-b), (III-d-e) and (III-g-l) and (IV-a) to (IV-l). Complex λem(nm) a Φ P (%) b τ1(ns) Complex λem(nm) a Φ P ( τ 1 (ns %) b ) (I-a) 472, 501 0.5 179 (III-a) 528 9.6 248 (I-b) 475, 505 0.5 177 (III-b) 476, 516, 546 1.8 194 (I-c) 502, 535 5.9 411 (III-d) 498 2.1 219 (I-d) 461, 490 0.7 184 (III-e) 542 4.0 208 (I-e) 511-550 3.7 224 (III-g) 593 0.1 191 (I-g) 593-652 <0.1 203 (III-h) 628 3.0 215 (I-h) 589, 627 3.0 202 (III-i) 548 0.3 227 (I-i) 522-567 <0.1 210 (III-j) 584, 635 3.0 197 (I-j) 586, 633 1.0 214 (III-k) 520, 558 6.1 649 (I-k) 518, 555 7.0 322 (III-l) 453, 479 1.7 159 (I-l) 453, 480 1.0 138 (IV-a) 473, 499 0.04 197 (II-a) 472, 500 0.5 210 (IV-b) 475, 502 0.03 197 (II-b) 475, 503 0.4 167 (IV-c) 504, 536 0.04 195 (II-c) 500, 534 4.6 319 (IV-d) 463, 491 0.03 228 (II-d) 461, 489 0.9 201 (IV-e) 528 0.17 200 (II-e) 514, 533 4.6 182 (IV-f) 445, 536 0.12 202 (II-h) 554-637 <0.1 185 (IV-g) 579 0.02 214 (II-i) 588, 629 3.0 199 (IV-h) 588, 626 0.07 178 (II-j) 524, 558 0.1 215 (IV-i) 615, 668 0.02 205 (II-k) 586, 632 1.0 206 (IV-j) 574, 648 0.01 196 (II-l) 517, 556 6.1 486 (IV-k) 518, 558 0.08 212 (II-h) 452, 478 0.8 209 (IV-l) 452, 477, 0.01 191 515, 547 a λem were measured in CH2Cl2 at room temperature (λexc = 365 nm for complexes (I-a-e), (I-i), (I-k), (II-a-e), (II-i), (II-k), (III-a-e), (III-k-l) and (IV-a-l), 470 nm for complexes (I-g-h), (I-j), (II-g-h), (II-j), and (III-g-j). b The emission phosphorescence quantum yields (Φp) were determined at room temperature using POPOP in hexane (Φ p = 97%) as the reference for complexes (I-a-e), (I-i), (I-k), (II-a-e), (II-i), (II-k), (III-a-e), (III-k-l) and (IV-a-m), and using Rhodamine B in ethanol (Φp = 65%) as the reference (I-g-h), (I-j), (II-g-h), (II-j), and (III-g-j). II.3. Singlet oxygen ( 1 O2) production of vectorized iridium(III) complexes. A. Singlet Oxygen Measurements. The detection of 1 O2 generation of iridium complexes was measured with 9,10-anthracenediyl-bis(methylene)dimalonic acid (ABDA) as an 1 O2 indicator and Ru(bpy)3Cl2 as a standard according to a modified reported method [16,17]. Experiments were conducted using ABDA (50 μM) in phosphate buffered solution (PBS, pH 7.4), the respective iridium complex, i.e. (I-e), (I-g), (I-h), (I-j), (II-e), (II-g), (II-h), (II-j), (III-i), (III-j), (III-k), (III-h), (IV-i), (IV-j), (IV-k), (IV-h) and Ru(bpy)3Cl2 (5 μM) in a mixture of H2O/CH3CN (50/50) with a ratio ABDA/complex of 1/10 and a final volume of 3 mL. ABDA oxidation was monitored by UV-vis spectrophotometry. The samples were irradiated with a blue custom-made LED plate (458 nm, 4.5 mWcm -2 ). During irradiation UV-vis absorption spectra were recorded at 5, 10, 15, 20, 30 and 45 min. The 1 O2 generation was followed by monitoring the absorption spectral change at 380 nm of ABDA versus time. B. Detection of singlet oxygen production. The ability of vectorized iridium complexes to produce singlet oxygen 1 O 2 upon light irradiation (blue custom-made LED plate (458 nm, 4.5 mWcm -2 ) was examined using the commonly applied singlet oxygen detection agent ABDA in PBS [16,17]. ABDA selectively reacts with 1 O 2 to give an endoperoxide which loses the characteristic anthracene absorption bands at around 350 to 410 nm. In order to evaluate the singlet oxygen production, the decrease of the ABDA absorption band at 380 nm was plotted versus time at 5, 10, 15, 20, 30 and 45 min. Upon irradiation with blue light, complexes (I-j), (III-h), (III-j) and (IV-j) show fast depletion of the ABDA absorbance at 380 nm with a fast complete consumption of ABDA for complexes (III-j) and (IV-j) (Figure 1). III. Cytotoxicity and photodynamic of the complexes according to the invention. III.1. Material and Methods. A. Cell culture. Cells were grown in humidified incubators at 37°C in 5% CO2. Murine MC3T3 osteoblast and NIH-3T3 fibroblast cells – used as non-tumor cell models – were cultured in α-MEM medium and DMEM medium supplemented with 10% fetal bovine serum (FBS) and 1% Penicillin/Streptomycin (P/S) antibiotics, respectively. Human T24 bladder, MGHU3 bladder, Scaber bladder, A549 lung, MCF7 breast, MiaPaCa2 pancreas cancer cells were cultured in DMEM medium supplemented with 10% FBS and 1% P/S antibiotics. Human ASPC-1 pancreas, PC- 3 prostate, DU-145 prostate, C4-2B prostate and 22rV1 prostate cancer cells were cultured in RPMI medium supplemented with 10% FBS and 1% P/S antibiotics. Human HeLa cervix and HepG2 liver cancer cells were cultured EMEM medium supplemented with 10% FBS and 1% P/S antibiotics. B. Cell Viability assay (MTT assay). MTT reagent (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) was used to determine cell death as originally described by Mosmann [18]. Briefly, cells were seeded from 5,000 to 10,000 cells/well in 24-well plates (1 mL) depending on the cell type and allowed to attach overnight. The complexes were prepared in DMSO. The concentration of the complexes was calculated based on the elemental composition of the complexes determined by the elemental analyses. All cell viability experiments were carried out with a fixed concentration of 0.1% (v/v) DMSO. After 72 h of treatment, cells were incubated at 37°C and 5% CO 2 with 25 µL of MTT solution (5 mg/ml; Sigma-Aldrich) in 24- well plates for 3 to 4 h. After solubilization with 500 µL of DMSO, formazan was quantified spectrophotometrically with a microplate reader at 570 nm absorbance (ClarioSTAR, BMG LabTech). GI50 values corresponding to the concentration that causes 50% inhibition of cell proliferation were calculated from dose-response curves obtained by nonlinear regression analysis (Prism 9.0, Graphpad Software). All the results were calculated from data obtained in at least three independent experiments performed in triplicate. C. Treatment conditions. Irradiation was conducted using an in-house device, a series of blue light LEDs selected according to the absorption spectra of the compounds at 458 nm wavelength with an emitted power of 9.6 Watts. The light fluence was measured at 458 nm with an optical power meter Thorlabs PM100A at different distances between the cell layer and the light source (5 and 10 cm). The data are presented in Figure 2A. A series of cell viability experiments were performed to evaluate the cytotoxic effect of light itself in three cell line models (non-tumor NIH-3T3, PC3 prostate cancer and T24 bladder cancer). For this purpose, cells were irradiated or not at 458 nm for different times (5 and 10 min) at different distances between the cell layer and the light source (5 and 10 cm). Cell viability was measured after 72 h of incubation. As shown in Figure 2B, minimal toxicity was observed for a distance of 10 cm between the light source and the cells, with no significant difference in toxicity between 5 or 10 min of irradiation. Based on these results, all further experiments were conducted with the following irradiation conditions: 10 min of irradiation at a distance of 10 cm. Two sets of experiments were conducted in parallel for each complex to be studied: 1. The cells were incubated with the different complexes (in the dark) for 72 h. 2. The cells were incubated for 8 h with the different complexes (in the dark), then irradiated for 10 min, followed by an incubation in the dark up to 72 h. III.2. Cytotoxicity and photodynamic of the series of biotin-vectorized compounds. Biotin is an essential B vitamin that acts as an important coenzyme in carbohydrate and lipid metabolism. With their rapid growth, cancer cells exhibit high metabolic activity, which is accompanied by a high utilization of essential vitamins. Consequently, receptors and/or transporters involved in the absorption of vitamins are overexpressed on the surface of cancer cells. For biotin, its cellular uptake is mediated by the sodium dependent multivitamin transporter also known as “SMVT” that is responsible for the translocation of hydrosoluble vitamins (pantothenic acid or Vit B5, Biotin or Vitamin B7 and α-lipoic acid). A number of studies have taken advantage of the overexpression of SMVT in a number of cancer cells and the simple structure of biotin to design effective tumor-targeting molecules conjugated to biotin, notably chemotherapeutic agents that showed superior cellular uptake and increased specificity. The cytotoxicity and photodynamic activities of the eleven biotin- vectorized compounds were first examined in two cell models (non-tumor fibroblastic NIH-3T3 and T24 bladder cancer). GI 50 values under dark and light irradiation conditions are summarized in Table 6. In the dark, the complexes showed no toxicity toward NIH-3T3 cells with GI 50 values ranging from 67 to over 250 µM, and showed moderate to no toxicity (GI 50 values ranging from 11.5 to 96 µM) against T24 cells. Complexes (I-a), (I-b), (I-c), (I-d), (I-i), and (I-l) did not show marked photosensitizing effects on tumor cells as shown in Table 7 (PI values ranging from 1.0 to 8.2, median = 1.4-fold, mean = 2.4-fold) in contrast to complexes (I-e), (I-g), (I-h), (I-j), and (I-k) (PI values ranging from 16.9 to 24.0, median = 19.3-fold, mean = 19.6-fold). Therefore, only complexes (I-e), (I-g), (I-h), (I-j), and (I-k) were evaluated in an additional non-tumor cell line (osteoblastic MC3T3) and five additional cancer cell lines (Scaber bladder, MGHU3 bladder, A549 lung, MCF7 breast and HeLa cervix). In the dark (Table 6), these complexes showed no toxicity toward non-tumor MC3T3 cells (GI50 values ranging from 25.8 to 56.8 µM). Complex (I-e) showed no activity in the dark on all tumor cell lines tested (GI50 values ranging from 96.4 to 221 µM) and its selectivity was low (SI values ranging from <1 vs. MC3T3 to >2.6 vs. NIH-3T3) (Table 6). In some cancer cell models (including Scaber and MGHU3 bladder, and HeLa cervix), complexes (I-j) and (I-k) had higher GI50 values than in non-tumor MC3T3 cells (Table 6). Complexes (I-g) (GI50 values ranging from 9.1 to 25.4 µM) and (I-h) (GI50 values ranging from 11.9 to 26.7 µM) showed a better selectivity (SI values ranging from 3.8 vs. MC3T3 to 7.6 vs NIH-3T3 for I-g and from 2.6 vs. MC3T3 to 6.3 vs NIH-3T3 for I-h) in all cancer cell models (with the exception of HeLa cervix) compared with non-tumor control cells (Table 6). In non-tumor cells (Table 7), the photosensitizing effects were low for complexes (I-e), (I-g), and (I-k) (PI values ranging from 1.2 to 2.4, median = 1.8-fold, average = 1.6-fold) yet quite significant for complexes (I-h) and (I-j) (PI values ranging from 6.0 to 26.2, median = 9-fold, mean = 12.5-fold). In all cancer cells, photosensitizing effects were markedly increased with PI values ranging from 3.7 to 17.2, median = 6.2-fold, mean = 8.4- fold for complex (I-e), PI values ranging from 4.6 to 16.9, median = 6.0-fold, mean = 7.5-fold for complex (I-g), PI values ranging from 12 to 24.8, median = 19.3-fold, mean = 19.0-fold for complex (I-h), PI values ranging from 18.9 to 49, median = 24.9-fold, mean = 28.0-fold for complex (I-j), and PI values ranging from 7.8 to 19.3, median = 12.2-fold, mean = 12.9-fold for complex (I-k) (Table 7). In conclusion, complex (I-g) and complex (I-k) showed the most selective effects under irradiated conditions, while complex (I-g) showed the highest selectivity under both dark and irradiated conditions and complex (I-k) showed little toxicity against tumor cells under dark conditions (Table 6 and Figure 3). Table 6 : Cytotoxicity (GI 50 values in µM) and selectivity index (SI) of the series of biotin-vectorized compounds (I).
Table 7 : Photosensitizing index (PI) of the series of biotin-vectorized complex.
III.3. Cytotoxicity and photodynamic of the series of salarisib-vectorized complexes. RAS proteins function as binary molecular switches that control intracellular signaling pathways involved in cellular processes such as proliferation, differentiation, or survival, in response to extracellular signals activating receptor tyrosine kinases. RAS proteins cycle between an inactive GDP- bound conformation and an active GTP-bound conformation. Mutations of RAS family genes (K-RAS, N-RAS and H-RAS) render the RAS protein constitutively active. Activating point mutations of RAS are not uncommon and comprise up to nearly one-third of all human cancers, including 90% of pancreatic ductal adenocarcinomas. The association of RAS proteins with membranes is absolutely required for their function. The RAS antagonist salirasib, also known as farnesylthiosalicylate (FTS), was designed to competitively inhibit the binding of GTP-bound RAS to its plasma membrane-anchorage domain (galectin), thereby inactivating RAS signaling by facilitating its degradation. Salirasib inhibits all isoforms of RAS and inhibits RAS-induced cell growth in several cell and animal models. Although salirasib did not show sufficient efficacy in Phase I and II clinical trials in humans, recent work has shown that it can be conjugated to improve its bioavailability. Thus, conjugated with heptamethine carbocyanine dyes, Salirasib has shown its interest as a tumor-targeting delivery system usable for tumor imaging in pancreatic animal models [19]. The cytotoxicity and photodynamic activities of the five salarisib- vectorized compounds were examined in two non-tumor cell models (NIH-3T3 and MC3T3) and four cancer cell lines carrying various Ras mutations (H-Ras- mutated T24 bladder, K-Ras-mutated MiaPaCa2 pancreas, K-Ras-mutated ASPC-1 pancreas, and K-Ras-mutated A549 lung). GI 50 values under dark and light irradiation conditions are summarized in Table 8. In the dark, complexes (II-e) and (II-j) showed moderate toxicity toward NIH-3T3 and MC3T3 cells with GI 50 values ranging from 7 to 12 µM, whereas the remaining compounds showed higher cytotoxicity (GI50 values ranging from 4 to 5.8 µM for complexes (II-g) and (II-k) and GI50 values ranging from 2 to 3.6 µM for complex (II-k). In cancer cells, specificity was moderate for complex (II-e) (SI values ranging from 2.2 to 6.1, median = 4.1-fold, mean = 4.1-fold), complex (II-h) (SI values ranging from 1.6 to 4.1, median = 2.7-fold, mean = 2.7-fold), complex (II-j) (SI values ranging from 0.6 to 3.6, median = 2.0-fold, mean = 2.0-fold), and complex (II-k) (SI values ranging from 2.0 to 4.7, median = 3.3-fold, mean = 3.1-fold) regardless of the cell type (Table 8). Compound complex (II-g) showed the highest selectivity toward cancer cells compared to non-tumor cells with SI values ranging from 5.8 to 14.4 (median = 10.3-fold, mean = 10.2-fold). Under blue light, complex (II-g) was the only one to display zero photosensitizing effect on non-tumor as well as on tumor cells, as shown in Table 9 (PI values ranging from 0.8 to 1 and from to 0.7 to 1.6, respectively). For all other compounds, the photosensitizing effect was significantly higher on cancer cells than on non-tumor models (PI values ranging from 1.1 to 5.0 and from 4 to 43.6, respectively). Complexes (II-h) and (II-j) showed the highest photosensitizing effect on cancer cells (PI values ranging from 18.1 to 37.8 and from 22.3 to 43.6, respectively) with minor to moderate effect on non-tumor models (PI values ranging from 2.6 to 2.9 and from 4.8 to 5.0, respectively). Collectively, complex (II-h) showed the most selective effects under irradiated conditions with a 25-fold increase in cell toxicity in cancer cells (GI 50 values ranging from 37 to 103 nM, mean = 66 nM) compared to non-tumor models (GI 50 values ranging from 1.37 to 1.85 µM, mean = 1.61 µM) as shown in Table 8 and Figure 4. Table 8 : Cytotoxicity (GI50 values in µM) and selectivity index (SI) of the salarisib- vectorized complexes. 5 Table 9 : Photosensitizing index (PI) of the salarisib-vectorized complexes.
III.4. Cytotoxicity and photodynamic of the series of PSMA-vectorized complexes. In what follows, the expression “PSMA-vectorized complexes” is to be understood “PSMA inhibitor-vectorized complexes” or “Lys-urea-Glu-vectorized complexes”. Prostate-specific membrane antigen (PSMA) is a transmembrane protein, which upon binding of a ligand is internalized into the cell. PSMA is mainly expressed in prostate tissue but can be found in lacrimal and salivary glands, kidneys, liver, spleen and small intestine. Its expression can also be detected in the neovasculature of some solid tumors including glioblastoma, thyroid cancer, gastric, breast, renal and colorectal cancers. Yet, its expression is dramatically increase (100- to 1,000-fold) on the cell membrane of nearly all prostatic cancer cells compared with normal non-target expression (on normal prostate epithelial cells, in the small intestine, renal tubular cells and the salivary glands), and increases in higher grades, metastatic, and castration-resistant cancers, potentially enabling PSMA to be used for diagnosis and therapy for prostate cancer. Several antibodies or small molecules targeting PSMA with very high affinity and specificity have been developed (i) for imaging, especially for biological recurrence or detection of oligometastases (e.g., PSMA small-molecule inhibitor HBED-CC, a class of urea-based PSMA inhibitors, labelled with 68 Gallium for positron emission tomography (FDA Approved), or (ii) for the potential treatment of metastatic castration-resistant prostate cancer (e.g., ongoing phase III trial with 177 Lutetium radiolabeled antibody HuJ591 or phase I with an anti- PSMA small-molecule drug conjugate with tubulysin B). The cytotoxicity and photodynamic activities of the ten PSMA-vectorized complexes were examined in the non-tumor cell model (NIH-3T3) and two prostate cancer cell models : PC-3 (that does not express PSMA) and C4-2b expressing PSMA. GI 50 values under dark and light irradiation conditions are summarized in Table 10. In the dark, all compounds showed no toxicity toward NIH-3T3 cells with GI50 values above 100 µM, and moderate to no toxicity in PC-3 (GI50 values ranging from 9.6 to >100 µM) and C4-2b (GI50 values ranging from 4.0 to >100 µM) cells. Compounds (III-h), (III-I), (III-j), and (III-k) showed the highest selectivity index in both PC-3 (SI values ranging from >1.7 to >10.4, median = 3.2- fold, mean = 4.6-fold) and C4-2b cells (SI values ranging from >6.7 to 25, median = 13.9-fold, mean = 14.9-fold), whereas compounds (III-a), (III-b), (III-d), (III-e), (III- g), and (III-l) no selectivity against PSMA-negative PC-3 cells and little selectivity (SI values ranging from 1 to 4.7, median = 2.2-fold, mean = 2.6-fold) against PSMA-positive C4-2b cells. Complexes (III-a), (III-b), (III-d), and (III-l) did not show any photosensitizing effect on non-tumoral NIH-3T3 and on PC-3 and C4-2b tumor cells as shown in Table 11. Complexes (III-e) and (III-g) showed photosensitizing effect on non-tumoral NIH-3T3 and a small photosensitizing effect against PC-3 (PI values from >2.1 to >7.0) and C4-2b (PI values from >1.2 to >3.8) tumor cells in contrast to complexes (III-h), (III-l), (III-j), and (III-k) (PI values ranging from 4.6 to 31.2 in PC-3 cells and from 5.5 to 21.7 in C4-2b). Therefore, only complexes (III-h), (III-l), (III-j), and (III-k) were evaluated in an additional non-tumor cell line (osteoblastic MC3T3) and two additional prostate cancer cell lines (the PSMA- negative DU145 and the PSMA-positive 22Rv1). Similar to NIH-3T3, complexes (III-h), (III-l), (III-j), and (III-k) showed low to no toxicity toward MC3T3 cells (GI 50 values ranging from 52.4 to > 250 µM). As shown in Table 10, SI values were higher in PSMA-negative cells (PC-3 and DU145) than in PSMA-positive cells (C4-2b and 22Rv1) when compared to both NIH-3T3 and MC3T3 cells in the dark with SI values ranging from >0.5 to 10.4-fold in PSMA-negative cells (median = 2.4-fold, mean = 4.1-fold) versus SI values ranging from 8 to >25.2-fold in PSMA-positive cells (median = 15-fold, mean = 16.8-fold). As shown in Table 11, under blue light, the photosensitizing effect on non- tumoral cells was moderate with PI values ranging from 1.8 to > 20-fold (median = 5.8-fold, mean = 6.9-fold), but much higher in cancer cells regardless of their PSMA status with PI values ranging from 4.6 to 146.4-fold (median = 20.1-fold, mean = 24.2-fold). Overall, complexes (III-h), and (III-k) showed the most selective effects under irradiated conditions with a >70-fold increase in cell toxicity in PSMA- positive cancer cells (GI50 values ranging from 140 to 410 nM, mean = 310 nM), and >14-fold increase in cell toxicity in PSMA-neagtive cancer cells (GI50 values ranging from 0.679 to 2.2 µM, mean = 1.6 µM) compared to non-tumor models (GI50 values ranging from 8.3 to 33.8 µM, mean = 22.8 µM) as shown in Table 10 and Figure 5.
Table 10 : Cytotoxicity (GI50 values in µM) and selectivity index (SI) of the PSMA-vectorized complexes.
Table 11 : Photosensitizing index (PI) of the PSMA-vectorized complexes. III.5. Cytotoxicity and photodynamic of the series of ferrocene-vectorized complexes. Ferrocene is the prototype of metallocenes with (i) low toxicity, (ii) excellent stability, and (iii) remarkable platform capabilities for the development of new organometallic compounds to treat a variety of diseases including cancer. The ability of ferrocene to induce ROS production via in situ oxidation (Fe(II)- Fe(III)) is the most important feature of ferrocene in its anticancer effects. Ferrocene has been shown to improve the profile of several anti-cancer agents including tamoxifen, nilutamide or taxanes. The cytotoxicity and photodynamic activities of the twelve ferrocene- vectorized complexes were first examined in two cell models (non-tumor fibroblastic NIH-3T3 and PC3 protate cancer). GI50 values obtained under dark and light irradiation conditions are summarized in Table 12. Under dark conditions, the complexes showed a minimal toxicity toward NIH-3T3 cells with GI50 values ranging from 11.8 to 62.8 µM (mean = 26.8 µM, median = 25.8 µM), and significant to moderate toxicity (GI50 values ranging from 850 nM to 21.6 µM, mean = 6.1 µM, median = 3.9 µM) against PC3 cells. Under irradiation conditions, complexes (IV-h), (IV-i), (IV-j), and (IV-k) showed the highest specificity towards PC3 cells (SI values ranging from 65.7 to 233.3, median = 80-fold, mean = 114.7- fold) as shown in Table 12. Complex (IV-b) showed a good specificity (SI value = 33.8) while the other compounds showed a lower specificity (SI values ranging from 2.8 to 13.7, median = 7.8-fold, average = 8.6-fold) as shown in Table 12. Based on these results, compounds (IV-h), (IV-i), (IV-j), and (IV-k) were further evaluated in an additional non-tumor cell line (osteoblastic MC3T3) and four additional cancer cell models (T24 bladder, A549 lung, MCF7 breast and MiaPaCa2 pancreatic). As for NIH3T3, the compounds showed limited toxicity in the dark against the non-tumor MC3T3 cell model with GI 50 values ranging from 10.0 to 17.1 µM (mean = 13.8 µM), and significant to moderate toxicity (GI 50 values ranging from 890 nM to 7.3 µM, mean = 3.8 µM) against the five tumor cell models. The photosensitizing effects of complexes (IV-h), (IV-i), (IV-j), and (IV- k) were low and similar in NIH-3T3 and MC3T3 non-tumoral cells with a mean PI value of 2.8-fold (Table 13). In tumor cells, complexes (IV-h) and (IV-j) showed high photosensitizing effect with PI values ranging from 13.0 to 24.6 (mean = 20.1-fold) and from 15.7 to 121.7 (mean = 39.8-fold), respectively. In contrast, complexes (IV-i) and (IV-k) showed very low photosensitizing effect in tumor cells (mean PI values of 1.6-fold and 1.8-fold, respectively). Collectively, complexes (IV-h) and (IV-j) showed the most selective effects under irradiated conditions with 29-fold and 39-fold increases in cell toxicity in cancer cells (GI50 values ranging from 58 to 277 nM, mean = 155 nM for complex (IV-h); and from 60 to 421 nM, mean = 228 nM for complex (IV-j)), respectively compared to non-tumor models (GI50 values ranging from 4.44 to 4.46 µM, mean = 4.45 µM and from 5.1 to 11.6 µM, mean = 8.4 µM, respectively) as shown in Figure 6.
Table 12 : Cytotoxicity (GI50 values in µM) and selectivity index (SI) of the ferrocene-vectorized complexes.
Table 13 : Photosensitizing index (PI) of the ferrocene-vectorized complexes. References [1] Zhu et al, 2007, “Simple Copper Salt-Catalyzed N-Arylation of Nitrogen- Containing Heterocycles with Aryl and Heteroaryl Halides”, J. Org. Chem., vol.72, pages 8535-8538. [2] Susumu et al, 2007, “Enhancing the Stability and Biological Functionalities of Quantum Dots via Compact Multifunctional Ligands”, J. Am. Chem. Soc., vol.129, pages 13987-13996. [3] Porta et al, 2019, “Repositioning Salirasib as a New Antimalarial Agent”, Med. Chem. Commun., vol.10, pages 1599–1605. [4] Maresca et al, 2009, “A Series of Halogenated Heterodimeric Inhibitors of Prostate Specific Membrane Antigen (PSMA) as Radiolabeled Probes for Targeting Prostate Cancer”, J. Med. Chem., vol.52, pages 347–357. [5] Lindsay & Hauser, 1957, “Aminomethylation of Ferrocene to Form N,N- Dimethylaminomethylferrocene and Its Conversion to the Corresponding Alcohol and Aldehyde”, C. R. J. Org. Chem., vol.22, pages 355–358. [6] Garces et al, 1988, “Synthesis, Structure, Electrochemistry, and Photophysics of Methyl-Substituted Phenylpyridine Ortho-Metalated Iridium(III) Complexes”, Inorg. Chem, vol.27, pages 3464–3471. [7] King & Watts, 1987, “Dual Emission from an Ortho-Metalated Ir(III) Complex”, J. Am. Chem. Soc, vol.109, pages 1589–1590. [8] Leo et al, 1971, “Partition coefficients and their uses”, Chem. Rev., vol. 71, pages 525-616. [9] Demas & Crosby, 1971, “The Measurement of Photoluminescence Quantum Yields”, J. Phys. Chem., vol.75, pages 991–1024. [10] Wu et al, 2010, “Dynamics of the Excited States of [Ir(Ppy)2bpy] + with Triple Phosphorescence”, J. Phys. Chem. A, vol.114, pages 10339–10344. [11] Sauvageot et al, 2014, “Iridium(III) Dipyridylamine Complexes: Synthesis, Characterization and Catalytic Activities in Photoredox Reactions”, Org. Chem. Front., vol.1, pages 639–644. [12] Lau et al, 2009, “Luminescent Cyclometalated Iridium(III) Polypyridine Indole Complexes-Synthesis, Photophysics, Electrochemistry, Protein- Binding Properties, Cytotoxicity, and Cellular Uptake”, Inorg. Chem., vol. 48, pages 708–718. [13] Li et al, 2012, “Cyclometalated Iridium(III)–Polyamine Complexes with Intense and Long-Lived Multicolor Phosphorescence: Synthesis, Crystal Structure, Photophysical Behavior, Cellular Uptake, and Transfection Properties”, Chem. Eur. J., vol.18, pages 13342–13354. [14] Yang et al, 2010, “Iridium Metal Complexes Containing N-Heterocyclic Carbene Ligands for Blue-Light-Emitting Electrochemical Cells”, Inorg. Chem., vol.49, pages 9891–9901. [15] Monti et al, 2013, “Charged Bis-Cyclometalated Iridium(III) Complexes with Carbene-Based Ancillary Ligands”, Inorg. Chem., vol. 52, pages 10292– 10305. [16] Yang et al, 2020, “Electron Storage Capability and Singlet Oxygen Productivity of a RuII Photosensitizer Containing a Fused Naphthaloylenebenzene Moiety at the 1,10-Phenanthroline Ligand”, Chem. Eur. J., vol.26, pages 17027–17034. [17] Feng et al, 2017, “Hyperbranched Phosphorescent Conjugated Polymer Dots with Iridium(III) Complex as the Core for Hypoxia Imaging and Photodynamic Therapy”, ACS Appl. Mater. Interfaces, vol. 9, pages 28319– 28330. [18] Mosmann, 1983, “Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays”, J Immunol Methods, vol.65, pages 55-63. [19] Zhao et al, 2020, “Mediated Imaging and Improved Targeting of Farnesylthiosalicylic Acid Delivery for Pancreatic Cancer via Conjugation with Near-Infrared Fluorescence Heptamethine Carbocyanine Dye”, ACS Applied Biomaterials, vol.2, pages 1129-1138.