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

Paper ID Volume ID Publish Year Pages File Format Full-Text
40047 45843 2013 8 PDF Available
Title
The chemo-enzymatic Baeyer–Villiger oxidation of cyclic ketones with an efficient silica-supported lipase as a biocatalyst
Abstract

•A novel, very active lipase on silica biocatalyst is proposed.•Silica with multimodal pore structure appears superior to MPS as enzyme support.•The catalysts show very good activity in chemo-enzymatic Baeyer–Villiger oxidation.•Stability and recyclability of the biocatalysts has been demonstrated.

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.Investigation of the biocatalysts performance (activity, stability, reusability) in BVO of cyclic ketones, using urea hydrogen peroxide as oxidant and ethyl acetate as both the peracid precursor and solvent, clearly demonstrated very large activity of MH biocatalysts. For the same lipase load activity decreased in the order MH-Me-L > MH-Oc-L > MH-Hd-L, with that of least active (MH-Hd-L) catalysts being even trice larger than of Novozyme-435 under equal mass basis. The biocatalysts showed good stability, even in the presence of 60% aq. hydrogen peroxide, and facile reuse. On this basis we proposed a general chemo-enzymatic BVO method for oxidation of cyclohexanones and cyclobutanone to obtain adequate lactones with high yields (80–98%).

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Keywords
Chemo-enzymatic Baeyer–Villiger reaction; Lactones; Cyclic ketones oxidation; Silica-supported lipase B; Enzyme carriers with hierarchical structure
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The chemo-enzymatic Baeyer–Villiger oxidation of cyclic ketones with an efficient silica-supported lipase as a biocatalyst
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Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volume 467, 2 October 2013, Pages 163–170
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
Get Full-Text Now
Don't Miss Today's Special Offer
Price was $35.95
You save - $31
Price after discount Only $4.95
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