The preparation of several N-monosubstituted trichlorothioacetamides by thionation of the corresponding acetamides, with the use of Heimgartner's reagent is described. In contrast to the corresponding amides which umdergo base-induced beta-elimination of chloroform, the title compounds undergo an unexpected rearrangement to thiooxamides. The reaction mechanism is discussed. (C) 1998 Elsevier Science Ltd. All rights reserved.
GERTSYUK, M. N.;DOROXOV, V. I.;SAMARAJ, L. I., ZH. ORGAN. XIMII, 1985, 21, N 4, 903-904
作者:GERTSYUK, M. N.、DOROXOV, V. I.、SAMARAJ, L. I.
DOI:——
日期:——
A novel synthesis of isocyanates and ureas via β-elimination of haloform
isocyanates via base-induced β-elimination of haloform N-monosubstituted trihaloacetamides is described. The rate of reaction exhibits a strong dependence on the nature of the trihalomethyl group. Thus, while the reaction of tribromoacetamides proceeds at room temperature and the reaction of trichloroacetamides requires heating in polar solvents, no reaction could be observed for any of the corresponding