PROCESS FOR PRODUCING a-SUBSTITUTED ESTER

摘要

An a-substituted ester can be produced by reacting a fluorosulfuric acid ester of an a-hydroxyester with a Grignard reagent in the presence of a zinc catalyst.  It is newly found that the reaction for producing a-substituted esters, in which the raw materials to be used are limited to trifluoromethanesulfonic acid esters (which are expensive compounds) previously, can proceed satisfactorily by using fluorosulfuric acid esters which are suitable for the mass production of the a-substituted esters.  When a fluorosulfuric acid ester having a high optical purity is used, an a-substituted ester having inversed stereochemistry can be produced at a high optical purity.  The process can solve all of the problems in conventional techniques and can be carried out on an industrial scale.