Enzyme catalyzed cross acyloin reactions via C-C bond cleavage

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2015
Bilir, Gökçil
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Enzyme-catalysis is an effective tool for asymmetric synthesis under environmentally-friendly conditions, with an increasing number of examples at industrial scale. The optically active enzyme scaffold creates a microenvironment responsible for the chirality generation. Benzaldehyde lyase (BAL; E.C. 4.1.2.38), is the first and well-known thiamine diphosphate (ThDP)- and Mg2+-dependent enzyme from Pseudomonas fluorescens Biovar I with its capability to catalyze various C-C bond cleavage and C-C bond formation. In this work, this enzyme was used for the synthesis of unsymmetrical acyloin products of a functionalized acetaldehyde (benzyloxyacetaldehyde) with (rac)-Benzoin derivatives to selectively obtain optically active functionalized acyloin product with promising biological activity and (S)-benzoin derivative which remains unreacted in the reaction medium. As a result of this trans-condensation reaction –with benzyloxyacetaldehyde as the acceptor and different derivatives of aromatic benzaldehydes as the donor most of the cases- stereoselective (R)-HPP derivatives were obtained enantioselectively. In the second part of this work, the synthesis of thiamine-amino acid conjugates and asymmetric thiazolium salts have been tried to be used as organocatalysis in benzoin condensation reactions.
Benzaldehyde., Lyases., Benzoin., Enzymes., Propiophenones., Pyrophosphates., Chemical reactions.
http://etd.lib.metu.edu.tr/upload/12619582/index.pdf
https://hdl.handle.net/11511/25314
Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats
G. Bilir, “Enzyme catalyzed cross acyloin reactions via C-C bond cleavage,” M.S. - Master of Science, Middle East Technical University, 2015.
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