Blaise Reaction of Ethyl 3-Bromodifluoromethyl-3-benzyloxyacrylate with Nitriles: A Convenient Synthesis of α-Difluorovinyl-Substituted β-Enaminoesters and β-Ketoesters

Weimin Peng; Jingwei Zhao; Shizheng Zhu

doi:10.1055/s-2006-926436

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Synthesis 2006(9): 1470-1474
DOI: 10.1055/s-2006-926436

PAPER

Blaise Reaction of Ethyl 3-Bromodifluoromethyl-3-benzyloxyacrylate with Nitriles: A Convenient Synthesis of α-Difluorovinyl-Substituted β-Enaminoesters and β-Ketoesters

Weimin Peng, Jingwei Zhao, Shizheng Zhu*
Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai 200032, P. R. of China
Fax: +86(21)64166128; e-Mail: zhusz@mail.sioc.ac.cn;

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Publication History

Received 2 November 2005
Publication Date:
07 April 2006 (online)

Abstract
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Abstract

The Blaise reaction between the zinc dienolate of ethyl 3-bromodifluoromethyl-3-benzyloxyacrylate and a variety of nitriles gave a series of α-difluorovinyl substituted β-enaminoesters in good yield, which readily underwent hydrolysis to the corresponding β-ketoesters. Direct coupling of this zinc dienolate with acyl chloride also furnished the same α-difluorovinyl substituted β-ketoester, though in low yield, while the tetrakis(dimethylamino)ethylene (TDAE) mediated reaction provided γ-CF₂ carbon and oxygen acylated products.

Key words

zinc dienolate - nitrile - Blaise reaction - β-enaminoesters - β-ketoester

References

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1

Current address: Department of Medicinal Chemistry and The Center for Protein Structure and Function, The University of Kansas, 1251 Wescoe Hall Drive, Malott Hall 4070, Lawrence, KS 66045-7562, USA.