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Synthesis 2003(8): 1262-1266
DOI: 10.1055/s-2003-39405
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Selective Conversion of N-Trichloroethoxycarbonyl (Troc) Groups into N-Acetyl Groups in the Presence of N-tert-Butoxycarbonyl (Boc) Protecting Groups

Xiangming Zhu, Richard R. Schmidt*
Fachbereich Chemie, Universität Konstanz, Fach M 725, 78457 Konstanz, Germany
Fax: +49(7531)883135; e-Mail: Richard.Schmidt@uni-konstanz.de ;
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Publication History

Received 19 February 2003
Publication Date:
26 May 2003 (online)

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Abstract

Deprotection of N-trichloroethoxycarbonyl (Troc) groups with zinc in acetic anhydride cleaves also N-tert-butoxycarbonyl (Boc) groups, thus liberating the amino groups, which are immediately N-acetylated. When this reaction is performed in the presence of triethylamine only Troc groups are selectively cleaved as demonstrated for several examples.

Key words

protecting groups - orthogonality - cleavage - zinc - amines

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