Enzymatic resolution of racemic secondary alcohols by lipase B from Candida antarctica

Chiral intermediates S(+)-2-pentanol and S(+)-2-heptanol were prepared by a lipase-catalyzed enzymatic resolution process. Among various lipases evaluated for the stereoselective acylation of racemic alcohols, lipase B from Candida antarctica catalyzed the acylation of the undesired enantiomer of racemic alcohols leaving the desired S(+)-alcohols unreacted. A reaction yield of 43-45% and an enantiomeric excess (e.e.) of >99% were obtained for S(+)-2-pentanol or S(+)-2-heptanol when the reaction was carried out using vinyl acetate or succnic anhydride as acylating agent. In an alternative process, an enantioselective hydrolysis of 2-pentyl acetate was demonstrated using lipase B giving S(+)-2-pentyl acetate and R-(-)-2-pentanol. A reaction yield of 45% and an e.e. of 98.6% were obtained for S(+)-2-pentyl acetate.