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Synthesis 2001(14): 2078-2080
DOI: 10.1055/s-2001-18060
SHORTPAPER
© Georg Thieme Verlag Stuttgart · New York

An Efficient Method for the Preparation of Benzylic Bromides

Peinian Liua, Yingchun Chenb, Jingen Deng*b, Yongqiang Tua
a Department of Chemistry & National Laboratory of Organic Chemistry, Lanzhou University, Lanzhou 730000, China
b Union Laboratory of Asymmetric Synthesis, Chengdu Institute of Organic Chemistry, the Chinese Academy of Sciences, Chengdu 610041, China
Fax: +86(28)5223978; e-Mail: jgdeng@cioc.ac.cn;
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Publikationsverlauf

Received 19 April 2001
Publikationsdatum:
09. August 2004 (online)

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Abstract

Substituted benzylic compounds are brominated with an excess of N-bromosuccinimide (NBS) in CCl4 to the corresponding polybrominated mixtures which are then debrominated with diethyl phosphite and N,N-diisopropylethylamine to afford the desired monobromides in satisfactory yields and high purity.

Key words

debromination - benzylic bromides - diethyl phosphite - N,N-diisopropylethylamine

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13

Two equivalents of NBS were necessary for the complete bromination of the methyl groups; see also Ref. [3] [14] [15]