Ionic liquids improve citronellyl ester synthesis catalyzed by immobilized Candida antarctica lipase B in solvent-free media†
Abstract
Several citronellyl esters (acetate, propionate, butyrate, caprate and laurate) were synthesized by immobilized Candida antarctica lipase B (Novozym) in high yields (>99%) using equimolar mixtures of citronellol and alkyl vinyl ester as substrates in solvent-free medium. The best results were obtained for citronellyl butyrate synthesis (17.4 µmol min−1 mg IME−1) at 70 °C, which could be improved up to two-fold by coating the biocatalyst particles with alkyl imidazolium-based ionic liquids, which favoured partitioning of the substrate and product molecules.