| abstract |
PURPOSE: To produce the threo-isomer of a 1,2-diol useful as an intermediate of pharmaceuticals, etc., economically, by reacting the corresponding ketone with a hydrosilane in an aprotic polar solvent in the presence of a fluorine anion, and hydrolyzing the reaction product with an acid or alkali. n CONSTITUTION: The ketone of formula I (R 1 and R 2 are alkyl, aryl, aralkyl or alkenyl; Z is protected OH, alkoxy or substituted amino) is made to react with the compound of formula IIR 3 WR 5 are alkyl, aryl, aralkyl, or alkixy; R 4 and R 5 may be H) in an aprotic polar solvent in the presence of fluorine anion preferably at -20W+30°C, and the reaction product is hydrolyzed with an acid or alkali to obtain the objective compound of formula III (Z' is Z or OH), in high selectivity. The objective compound of formula III is an intermediate of threo-2-amino-alcohol and amino-sugar such as pseudoephedrine useful as pharmaceuticals, asymmetric modifier, optical resolution agent, etc. n COPYRIGHT: (C)1985,JPO&Japio |