作者:S. Braverman、M. Cherkinsky、L. Kedrova、A. Reiselman
DOI:10.1016/s0040-4039(99)00372-x
日期:1999.4
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
描述了通过卤代N-单取代的三卤代乙酰胺的碱诱导的β-消除新合成的异氰酸酯。反应速率显示出对三卤代甲基基团的强烈依赖性。因此,尽管三溴乙酰胺的反应在室温下进行并且三氯乙酰胺的反应需要在极性溶剂中加热,但是对于任何相应的三氟衍生物都没有观察到反应。从稳定且容易获得的三卤代乙酰胺中去除卤素的这种新颖的β-消除方法可用于尿素的“一锅法”合成,避免了使用光气和分离异氰酸酯。