Hydrogen attack, incubation

Biochemical reduction of a,/3-unsaturated ketones using microorganisms (best Beauveria sulfurescens) takes place only if there is at least one hydrogen in the /3-position and the substituents on a-carbons are not too bulky. The main product is the saturated ketone, while only a small amount of the saturated alcohol is formed, especially in slightly acidic medium (pH 5-5.5). The carbonyl is attacked from the equatorial side. Results of biochemical reduction of 5-methylcyclohex-2-en-l-one are illustrative of the biochemical reduction by incubation with Beauveria sulfurescens after 24 hours 74% of the enone was reduced to 3-methylcyclohexanone and 26% to 3-methylcy-clohexanol containing 55% of cis and 45% of trans isomer. After 48 hours the respective numbers were 70% and 30%, and 78% and 22%, respectively [878]. 

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