Optically active alcohol - Le recipe

摘要

PURPOSE:To obtain the title compound of high optical purity which is used as an intermediate of medicines and in liquid crystals, by conducting asymmetric hydrogenation of a beta-ketoacid using a ruthenium-optically active phosphine complex which is relatively inexpensive as a catalyst. CONSTITUTION:A beta-ketoacid of formula I [R is alkyl, trifluoromethyl, aryl; R2 is OR4 (R4 is alkyl), SR5 (R5 is alkyl, phenyl), NR6R7 (R6, R7 are H, alkyl, benzyl); R3 is H, halogen, alkyl; R1 and R3 may form a methylene chain] such as methyl acetoacetate is asymmetrically hydrogenated using a ruthenium- optically active phosphine complex, such as a complex of formula II (BINAP is 2,2'-bis(diphenylphosphino)-1,1-binaphthyl) as a catalyst to give an optically active alcohol of formula III such as methyl (3R)-(-)-3-hydroxyacetate.