Process for preparing valproic acid

摘要

A process for preparing valproic acid which comprises: (I) producing a 2,2-dipropyl acetoacetic acid ester from an acetoacetic acid ester, (II) deacetylating the 2,2-dipropyl acetoacetic acid ester with an alcohol to give a valproic acid ester, and (III) hydrolyzing the valproic acid ester. In the process of the present invention, valproic acid can be prepared in a high yield as not less than 85% by mole and by-products such as alpha -propyl- beta -ethyl acrylic acid and its esters which cannot be easily separated from valproic acid, are not entirely produced.