Synlett 2007(9): 1473-1474  
DOI: 10.1055/s-2007-980374
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

2,2,2-Trichloroethyl Chloroformate (TrocCl)

Ederson Oliveira dos Reis*
Departamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio de Janeiro, Centro de Tecnologia, Bloco A, 6° andar, Ilha do Fundão, Cidade Universitária, Rio de Janeiro-RJ, Brasil, CEP 21949-900.
e-Mail: ederson@iq.ufrj.br;
Further Information

Publication History

Publication Date:
23 May 2007 (online)

Introduction

2,2,2-Trichloroethyl chloroformate (TrocCl, CCl3CH2OCOCl, bp 171-172 °C,) is a stable chloro­formate which acylates aliphatic and aromatic hydroxyl and amino groups under mild conditions. [1] [2] This reagent is commercially available and has been widely used in ­regio-, chemo-, and stereoselective syntheses. The Troc group shows a sharp and charactereristic proton singlet at δ = 4.68-4.89 ppm, which makes its presence or absence easily detectable by 1H NMR spectroscopy. [3-5] TrocCl has proved to be an excellent reagent for dealkylation of ­secondary or tertiary amines, with good selectivity, thus producing clean reaction products. [1] [3] Moreover, TrocCl is a suitable substrate for Mitsunobu inversion reactions. [6] Recently, the total synthesis of Aprotoxin A with protection and deprotection of an allyl ester intermediate with TrocCl was described. [7] Several methods of Troc ­removal have been described, leaving a wide variety of other functional groups unaffected. [7,8] [10] The following ­examples highlight the importance and early applicability of this ­reagent in organic chemistry.

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