PURPOSE: To inexpensively obtain benzothioxanthene dyestuffs of high purity in high yield by simultaneously diazotizing and cyclizing 3-(2'-aminophenylthio) benzoanthrone in a polar aprotic solvent in the presence of water.
CONSTITUTION: 3-(2'-Aminophenylthio)-benzoanthrone represented by formula I (wherein R1 and R2 are each H, 1-2C alkyl, alkoxy or chlorine; R3 and R4 are each H or bromine) is prepared and simultaneously diazotized and cyclized in a polar aprotic solvent (e.g. N-methylpyrrolidone-2) in the presence of water to obtain benzothioxanthene dyestuffs represented by formula II. By this constitution, the addition of copper (salt) and an acid binding agent can be omitted and a compd. represented by formula II suitable as fluorescent dyestuffs for synthetic fibers and synthetic resin can be produced in a high yield of 95% with high purity.
| JPS55145763 | ANTHRAQUINONE DERIVATIVE * PRODUCTION AND USE |
| JPS541334 | ANTHRAQUINONE COMPOUND |
| JPS62215902 | PRODUCTION OF COLOR FILTER |
EEBERUHARUTO GURIMU
UUUE NITSUKERU
MANFUREETO SHIYUROOTO
HERUBERUTO UIRE
