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Synthesis 2009(19): 3350-3352  
DOI: 10.1055/s-0029-1216971
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© Georg Thieme Verlag Stuttgart ˙ New York

A Practical Synthesis of β-Keto Thioesters by Direct Crossed-Claisen Coupling of Thioesters and N-Acylbenzotriazoles

Guoqiang Zhou, Daniel Lim, Fang Fang, Don M. Coltart*
Department of Chemistry, Duke University, Durham, NC 27708, USA
Fax: +1(919)6601605; e-Mail: don.coltart@duke.edu;
Further Information

Publication History

Received 13 June 2009
Publication Date:
28 August 2009 (online)

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Abstract

Thioesters undergo chemoselective soft enolization and acylation with N-acylbenzotriazoles on treatment with MgBr2˙OEt2 and i-Pr2NEt to give β-keto thioesters. Prior enolate formation is not required and the reaction is conducted using untreated dichloromethane open to the air.

Key words

soft enolization - crossed-Claisen condensation - acylation - thioester - C-C coupling reaction

    References

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