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Synthesis 2007(3): 478-482  
DOI: 10.1055/s-2006-958959
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© Georg Thieme Verlag Stuttgart · New York

A Direct Aldol Addition of Simple Thioesters Employing Soft Enolization

Guoqiang Zhou, Julianne M. Yost, Don M. Coltart*
Department of Chemistry and the Center for Chemical Biology, Duke University, Durham, NC 27708, USA
Fax: +1(919)6685483; e-Mail: don.coltart@duke.edu;
Further Information

Publication History

Received 6 September 2006
Publication Date:
21 December 2006 (online)

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Abstract

Simple thioesters undergo direct aldol addition to aldehydes in the presence of magnesium bromide-diethyl ether and N,N-diisopropylethylamine using untreated, reagent grade dichloromethane under atmospheric conditions. The reactions proceed extremely rapidly and in excellent yield.

Key words

direct aldol reaction - ester - magnesium - thioester - thiol

    References

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5

All thioesters used in this work, with the exception of commercially available 7, 10, and 11, were prepared via acylation of the corresponding commercially available thiols.

6

Aldrich ACS reagent grade, ≥99.5%.