Production manner null of the optically active substance which uses the asymmetrical reducing agent, and the said asymmetrical

摘要

PURPOSE: To provide an asymmetric reducing agent capable of efficiently producing an optically active amine derivative, an optically active alcohol derivative, etc., from an oxime derivative, a ketone derivative, etc. ;CONSTITUTION: An asymmetric reducing agent obtained from an optically active oxazoborolidine of formula I or II (R¹ is an alkyl, allyl, an aryl, an aralkyl or a halogen; R us an alkyl, an aryl or an aralkyl; R²' is H or R²; R³ is an alkyl, an aryl or an aralkyl; * is an asymmetric carbon), e.g. (4S)(5R)-1,3,2-(2- methyl-4,5-diphenyl)oxazaborolidine, a metal borohydride and an acid, preferably a Lewis acid or sulfuric acid. An optically active amine derivative of formula IV can be synthesized by reacting this asymmetric reducing agent with an anti-form substance of an oxime derivative of formula III (R⁴ is H, an alkyl an aralkyl or an alkyl-substrtuted silyl; R⁵ and R⁶ are each an alkyl, an aryl or an aralkyl), its syn-form substance or their mixture rich in one substance of them. According to the same method, an optically active alcohol derivative of formula VI can be synthesized from a ketone derivative of formula V (R⁷ and R⁸ are each R⁵ and R⁶).;COPYRIGHT: (C)1995,JPO