Room-Temperature Debenzylation of N-Benzylcarboxamides by N-Bromosuccinimide

Liping Kuang; Jing Zhou; Sheng Chen; Ke Ding

doi:10.1055/s-2007-990795

PAPER

Room-Temperature Debenzylation of N-Benzylcarboxamides by N-Bromosuccinimide

Liping Kuang^a,b, Jing Zhou^a, Sheng Chen^a, Ke Ding*^a
^a Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou International Business Incubator A-3, Guangzhou Science Park, Guangzhou, 510663, P. R. of China
^b Graduate School of the Chinese Academy of Sciences, 19 Yuquan Rd, Beijing 100049, P. R. of China
Fax: +86(20)32290606; e-Mail: ding_ke@gibh.ac.cn ;

Abstract

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Abstract

A simple and highly efficient method has been developed with which to cleave the N-benzyl group on N-mono- or disubstituted carboxamides using N-bromosuccinimide (NBS) at room temperature. All the 31 substrates examined showed moderate to excellent deprotection yields. Our study also indicated that the debenzylation may involve an oxygen/light initiated free radical mechanism.

Key words

NBS - debenzylation - carboxamides - free radical

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