Synlett 2005(16): 2495-2497  
DOI: 10.1055/s-2005-917077
LETTER
© Georg Thieme Verlag Stuttgart · New York

Mild and Efficient Method for Decarboxylative Bromination of α,β-Unsaturated Carboxylic Acids with Dess-Martin Periodinane

Vikas N. Telvekar*, Nitin D. Arote, Omkar P. Herlekar
Department of Pharmaceutical Sciences and Technology, University Institute of Chemical Technology, Matunga, Mumbai 400019, India
Fax: +91(22)24145614; e-Mail: vikastelvekar@rediffmail.com;
Further Information

Publication History

Received 14 March 2005
Publication Date:
21 September 2005 (online)

Abstract

A simple and mild method for decarboxylative bromination of α,β-unsaturated carboxylic acids has been developed using Dess-Martin Periodinane (DMP) in combination with tetraethylammonium bromide (TEAB) at room temperature. High yields of the corresponding bromoalkenes were obtained.

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General experimental procedure: To a stirred suspension of DMP (1.1 equiv) in anhyd CH2Cl2 (15 mL) was added TEAB (1.1 equiv) in one portion. The resultant mixture was stirred r.t. for 5 min followed by addition of α,β-unsaturated carboxylic acid (1.0 equiv) and stirring was continued at r.t. until the starting material had been completely consumed (TLC). The reaction mixture was diluted with CH2Cl2 and washed successively with 10% aq sodium bisulfite solution (2 × 15 mL), 10% NaHCO3 (2 × 15 mL), H2O (1 × 10 mL), and brine (1 × 10 mL). The organic layer was dried over Na2SO4 and concentrated in vacuo. The residue obtained was purified by silica gel column chromatography (10% EtOAc-hexane) to afford pure bromoalkenes.