Enoyl acyl carrier protein reductase (FabI) catalyzed asymmetric reduction of the CC double bond of α,β-unsaturated ketones: preparation of (R)-2-alkyl-cyclopentanones

Enoyl-ACP reductase (FabI) was identified as a non-OYE ‘ene’-reductase for asymmetric reduction of the CC double bond of α, β-unsaturated ketones. Reduction of several 2-alkylidenecyclopentanones with A-FabI and E-FabI gave (R)-2-alkylcyclopentanones in 95–90% and 70–81% ee, respectively. The product ee was improved to 99–98% in high yield by subsequent one-pot biooxidation.