Lipases Aided Esterification of (2,2-Dimethyl-1,3-dioxolan-4-yl)methanol

Racemic solketal (2,2-Dimethyl-1,3-dioxolan-4-yl)methanol 1, was treated with carboxylic acids of varying chain length or their vinyl esters in the presence of different lipases. The esterification reaction was carried out in n-hexane or diisopropyl ether as a solvent. The yield of the solketal esters and their enantiopurity were satisfactory, as indicated by gas chromatography using chiral column. Lipases from Rhizopus oryzae and Pseudomonas fluorescence gave the best enantiomeric excess (ee) when the solketal was treated with vinyl butyrate in a solution of diisopropyl ether at room temperature.