STUDIES ON THE ENANTIOSELECTIVITY IN THE LIPASE-CATALYZED SYNTHESIS OF MONOACYLGLYCEROLS FROM ISOPROPYLIDENE GLYCEROL

The regioselective lipase-catalyzed acylation of isopropylidene glycer ol using different vinyl esters as acyl donors in toluene was studied. Reaction progress and enantioselectivity were monitored by gas chroma tography using a permethylated beta-cyclodextrin phase. All vinyl este rs were completely converted after 20 to 24 h and it was found that th e S-enantiomer reacted faster. Lower enantiomeric excess were found us ing e. g. vinyl palmitate (18 %ee) compared to e. g. vinyl butyrate (4 2 %ee) with crude lipase from Pseudomonas cepacia. Immobilization usin g the sol-gel method resulted in higher remaining activities (up to 69 %) and increased enantioselectivity E (up to 8.5).