ALCOHOLS AS ENANTIOSELECTIVE INHIBITORS IN A LIPASE-CATALYZED ESTERIFICATION OF A CHIRAL ACYL DONOR

Increased reaction rates and increased enantioselectivities were obser ved with decreased concentrations of n-alkanols when resolving 2-methy ldecanoic acid by esterification catalysed by immobilised lipase from Candida rugosa at controlled water activities in cyclohexane. The enan tioselectivity was found to be independent of the water activity in th e reaction medium at the n-heptanol concentrations investigated. Howev er, when n-decanol was used as the acyl acceptor, not only the alcohol concentration but also the water activity in the reaction medium, inf luenced the enantioselectivity. The results obtained showed that the l ow enantioselectivity seen at a high alcohol concentration could be ex plained by the alcohol influencing the apparent V-max(S), and V-max(R) differently.