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Phase-transfer catalysed asymmetric epoxidation of enones using N-anthracenylmethyl-substituted Cinchona alkaloids

✍ Scribed by B. Lygo; P.G. Wainwright

Publisher
Elsevier Science
Year
1999
Tongue
French
Weight
787 KB
Volume
55
Category
Article
ISSN
0040-4020

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✦ Synopsis

A study into the enantioselecfive epoxidation of a, [3-unsatma~ ketones utilising Cinchona alkaloidderived q,m_~nmT -mmonium ~-Wansfer catalysts beating m N-an~racenylmethyl function is presented. It has been found that the O-benzyl derivatives of these catalysts in conjunction with sodium hypcchloflto give high enantio-~ diastefeoselectivities in the epoxidation of a range of mbslrates RtCHfCHCOR 2, where RlffialkTl or aryl end R2=myl. In the cases where R2~tyl high en~tioselectivity has also been observed, however the rate of reaction is substantially reduced. Appfication of this process to the enantioselective synthesis of a range of trans.vt, [~-epoxy ketones (e.e. 71-90%) is presented.

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## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

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