Oxidative ring opening reactions of a-hydroxy ketones

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2008

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Aybey, Ayşe

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Chiral polyfunctionalized 1,5-dicarbonyl compounds are important synthetic intermediates and starting materials for many biologically active compounds so their synthesis has a great importance in the literature. In the first step, 1,3-cyclohexandione and other b-diketone derivatives are protected under acid catalyzation and their corresponding b-keto enol ether derivatives are obtained. These b-keto enol ethers are then converted to a-acetoxy enones in racemic form by Mn(OAc)3 mediated oxidation. Enzymatic kinetic resolution is applied to the racemic acetoxy enones by using different lipases and enantiomerically pure a-acetoxy and hydroxy enones are obtained. Then, dicarbonyl derivatives are obtained by hydrolizing racemic a-acetoxy enones. Oxidative cleavage of racemic a-acetoxy diketones in the presence of oxone gives corresponding racemic 1,5-dimethyl ester derivatives. By using this reaction as a reference, same reactions are applied to the chiral a-acetoxy and hydroxy diketones in order to synthesize chiral a-acetoxy and hydroxy 1,5-diester derivatives.

Subject Keywords

Chemistry, Organic

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http://etd.lib.metu.edu.tr/upload/3/12609279/index.pdf
https://hdl.handle.net/11511/17510

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

A. Aybey, “Oxidative ring opening reactions of a-hydroxy ketones,” M.S. - Master of Science, Middle East Technical University, 2008.