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 proces. 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.