REGIOSELECTIVE OR ENANTIOGENIC ELECTROCHEMICAL AND MICROBIAL REDUCTIONS OF 1,2-DIKETONES

The electrochemical and microbial reduction of 1,2-diketones have been studied and the results compared among themselves and with those of p revious works. The electrochemical reduction is highly selective and a llows alpha-ketols to be obtained. The latter, being unreducible at th e fixed potential used, never form diols. The anaerobic microbial redu ction by Proteus mirabilis proves to be more chemo-and regioselective than that previously performed with other microorganisms. After two ho urs of incubation, the enantiomerically pure (2S)-alpha-ketols are iso lated in high yield except in the case of 1,2-cyclohexanedione, for wh ich the (1S,2S) diol is formed for all reaction times. The microbial r eduction of the electrochemically generated racemic 2-hydroxycyclohexa none yields the sole (1S,2S) diol.