Synthesis of Optically Active .GAMMA.-Lactones with Lipase Catalyst

Lipase-catalyzed transesterification of racemic N-benzyl-4-hydroxyalkanamides with vinyl acetate proceeded enantioselectively to afford the reacted (S)-N-benzyl-4-acetoxyalkanamides and the unreacted (R)-N-benzyl-4-hydroxyalkanamides, which were separated easily by recrystallization in n-hexane. Both enantiomers were converted easily to optically active 4-substituted γ-lactones.