Temperature-dependence of enantioselectivity and desymmetrization in the acetylation of 2-mono- and 2,2-di-substituted 1,3-propanediols by a novel lipase isolated from the yeast Cryptococcus spp. S-2

The effect of temperature on enantioselectivity and desymmetrization in the acetylation of 2-phenyl-1,3-propanediol (1a), 2-benzyl-1,3-propanediol (1b), 2-methyl-2-phenyl-1,3-propanediol (1c) and 2-benzyl-2-methyl-1,3-propanediol (1d) by a novel lipase (CSL) isolated from the yeast Cryptococcus spp. S-2 was studied. Desymmetrization of 1a, 1c and 1d by CSL-catalyzed acetylation was observed in the temperature range of ?20°C to 40°C, while diacetylation of 1b occurred considerably even at 0°C. The kinetic parameters of the selectivity indicated that the acetylation of 1a is an entropy controlled process whereas the reaction of 1c and 1d is mainly controlled by the enthalpy term. In the monoacetylation of the diol 1d, the preferred configuration in the enantiomeric induction by CSL was opposite to that of immobilized porcine pancreatic lipase (PPL).