Synthesis 2006(9): 1470-1474  
DOI: 10.1055/s-2006-926436
PAPER
© Georg Thieme Verlag Stuttgart · New York

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;
Further Information

Publication History

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

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.

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