The chemo-enzymatic Baeyer–Villiger oxidation of cyclic ketones with an efficient silica-supported lipase as a biocatalyst Original Research Article

The synthesis and characterisation of new, silica-supported lipase biocatalysts and studies of their performance in Baeyer–Villiger oxidation (BVO) of cyclic ketones to lactones were described. Biocatalysts were obtained by immobilisation of Candida Antarctica lipase B onto siliceous materials with multimodal pore structure (MH) and also on typical SBA-15, chemically modified with organosilanes terminated with methyl, octyl and hexadecyl group. Biocatalysts structure was characterised by nitrogen adsorption and TEM/SEM imaging. The lipase presence was confirmed by FTIR spectroscopy, whereas protein loads were obtained from thermogravimetric data. They appeared to be notably larger for MH catalysts than SBA-15s and correlated with surface hydrophobicity of supports which decreased in the order Hd > Oc > Me, from 198 to 80 mg/g, for MH-Hd-L and MH-Me-L biocatalysts, respectively.