PAPER	Synthesis 2006: 1087-1092   DOI: 10.1055/s-2006-926386
© Georg Thieme Verlag Stuttgart · New York
A Convenient Synthesis of 2,2-Dibromo-1-arylethanones by Bromination of 1-Arylethanones with the H2O2-HBr System
Alexander O. Terent'ev*, Sergey V. Khodykin, Igor B. Krylov, Yuri N. Ogibin, Gennady I. Nikishin
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect 47, 119991 Moscow, Russia Fax: +7(95)1355328; e-Mail: terentev@ioc.ac.ru;
Received 27 June 2005

Abstract

1-Arylethanones and related compounds are brominated in dioxane with the H₂O₂-HBr_aq system, resulting in the replacement of two hydrogen atoms in the methyl group with bromine. The reaction is also accompanied by bromination of the aromatic ring provided that the latter contains electron-donating substituents. The reaction proceeds rapidly (20 min) and results in complete conversion of ketones to give 2,2-dibromo-1-arylethanones in yields up to 86%.

Key words

acetophenones - 1-arylethanones - 2,2-dibromo-1-aryl­ethanones - bromination - hydrogen peroxide