PURPOSE: To obtain industrially and advantageously the titled compound useful as a germicide, etc., by asymmetrically reducing a ketonic compound with a boron hydride reducing agent obtained by reacting an optically active amino- alcohol with borane in a specific proportion.
CONSTITUTION: A ketonic compound expressed by formula I (R1 is 3W8C cycloalkyl, 5W8C cycloalkenyl, halogen 1W4C alkyl, 1W4C haloalkyl, etc.; R2 is imidazol-1-yl or 1,2,4-triazol-1-yl) as a raw material is asymmetrically reduced with a boron hydride reducing agent obtained by reacting an optically active amino- alcohol expressed by formula II (R3 is 1W8C alkyl, 6W10C aryl, etc.: R4 is H, 1W6C alkyl or 7W16C aralkyl, R5 is H, 1W10C alkyl, 7W16C aralkyl, etc.; * is asymmetric carbon) with borone in an amount of 0.7W1.8 equivalents based on the amino-alcohol to give the aimed compound expressed by formula III.
SUZUKAMO TAKEO
SAKITO YOUJI
NISHIOKA TOSHIO
