Rhizopus arrhizus mediated asymmetric reduction of alkyl 3-oxobutanoates

Abstract

Alkyl 3-oxobutanoates (alkyl: methyl, ethyl, allyl, isobutyl, t-butyl) were reduced enantioselectively to the corresponding ( S)-alcohols by the fungus Rhizopus arrhizus and other Rhizopus sp. The best result obtained was with t-butyl 3-oxobutanoate, which was reduced by R. arrhizus with 99% enantiomeric excess and ∼68% isolated yield.