Enzymes in organic synthesis. 30. Reaction conditions – control of enantiomeric purities. Horse liver alcohol dehydrogenase-catalyzed reductions of 2-alkylcyclohexanones and their thiopyran analogs

The effects of buffer, pH, reaction time, and [enzyme]/[substrate] ratio on the enantiomeric purities of the alcohol products of horse liver alcohol dehydrogenase-catalyzed reductions of (±)-α-alkylcyclohexanones and -tetrahydrothiopyranones have been studied. For poor substrates of this type, formation of enantiomerically pure products is assured when pH 8 and < 0.5 × 10−4 [E]/[S] ratio conditions are used.