Candida rugosa lipase-mediated enantioselective acetylation studies on (±)-3-arylmethyl-3-hydroxymethyl-2,3-dihydro-1-benzopyran-4(H)-ones

Candida rugosa lipase, catalyzed enantioselective acetylation reactions have been performed on novel (+/-)-3-arylmethyl-3-hydroxymethyl-2,3-dihydrobenzopyran-4-ones in diisopropyl ether. The Candida rugosa lipase-catalyzed acetylations exhibit the enantiomeric separation of the racemic compounds 5a-g, the enantioselectivity of the reaction has been found to be highly dependent on the structure of the substrate. The enantiomeric excess (ee) values are determined by H-1 NMR spectral analysis of their O-acetylmandelic acid esters and highest enantiomeric excess obtained is 79% in case of 5c.