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Synthesis 2006(5): 803-806  
DOI: 10.1055/s-2006-926334
PAPER
© Georg Thieme Verlag Stuttgart · New York

An Efficient Synthesis of Difluoropropargyl Bromides

Bo Xu, Masayuki Mae, Jiyoung A. Hong, Youhua Li, Gerald B. Hammond*
Department of Chemistry, University of Louisville, Louisville, Kentucky 40292, USA
Fax: +1(502)8523899; e-Mail: gb.hammond@louisville.edu;
Further Information

Publication History

Received 12 September 2005
Publication Date:
07 February 2006 (online)

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Abstract

High yields of γ-alkyl, -silyl and -aryl-substituted difluo­ropropargyl bromides have been obtained by monitoring concentration and temperature in the reaction between CF2Br2 and γ-substituted lithium acetylide. γ-Silyl substituents afforded the corresponding α,α,α-difluorobromopropargyl alcohols in good yields via cleavage of tetrabutylammonium fluoride in the presence of an aldehyde.

Key words

alkynylation - fluorine - building block - substituent effect

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1

New address: Sumitomo Chemical Ltd. 4-2-1, Takatsukasa, Takarazuka, Hyogo 665-8555, Japan.

14

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