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Synthesis 2009(1): 56-58  
DOI: 10.1055/s-0028-1083278
SHORTPAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Direct Carbon-Carbon Bond Formation via Soft Enolization of Thioesters: An Operationally Simple Mannich Addition Reaction

Julianne M. Yost, Michelle R. Garnsey, Mark C. Kohler, 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 21 October 2008
Publication Date:
12 December 2008 (online)

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Abstract

Thioesters undergo soft enolization and direct Mannich addition to sulfonylimines on treatment with magnesium bromide ethyl etherate and N,N-diisopropylethylamine. The reactions proceed readily with a range of sulfonylimines and, in the case of 2,4,6-triisopropylphenyl thiopropionate, give moderate to good syn dia­stereoselectivity.

Key words

enolates - imines - Mannich addition reactions - magnesium - thioesters

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7

1 and 6 are commercially available (Aldrich).