Synthesis and Reactivity of <i>N</i>-Alkyl Carbamoylimidazoles: Development of <i>N</i>-Methyl Carbamoylimidazole as a Methyl Isocyanate Equivalent
作者:Petar A. Duspara、Md. Sadequl Islam、Alan J. Lough、Robert A. Batey
DOI:10.1021/jo302084a
日期:2012.11.16
results in the release of MeNH2 with simultaneous activation of the CDI as its protonated form. Other primary ammonium hydrochloride salts, including protected α-amino acid salts, give excellent yields of the corresponding N-alkyl carbamoylimidazoles and serve as alkyl isocyanate surrogates. The resultant N-alkyl carbamoylimidazoles can be converted to ureas in high yields without the formation of intermediary
描述了由1,1-羰基二咪唑(CDI)和MeNH 3 Cl高产率地合成N-甲基氨基甲酰咪唑。该产物是易储存的结晶晶体,是水稳定的化合物,可作为异氰酸甲酯(MIC)的替代物进行反应。的反应ñ -甲基在碱如三乙胺与亲核试剂如胺,被保护的和未受保护的氨基酸,硫醇和醇发生的存在carbamoylimidazole。N-甲基脲,氨基甲酸酯和硫代氨基甲酸酯的产物以良好或优异的收率获得,反应在有机溶剂或水中发生。合成N的协议-甲基氨基甲酰咪唑既具有可扩展性又具有通用性,其定量收率范围为300 mg至20 g。该方法的成功取决于CDI与铵盐而不是游离胺的反应,从而导致N-甲基氨基甲酰咪唑的收率显着提高。该反应大概涉及质子从MeNH 3 Cl到CDI的转移,这导致MeNH 2的释放以及CDI的质子化形式同时被激活。包括受保护的α-氨基酸盐在内的其他伯氢氯化盐可得到相应的N-烷基氨基甲酰咪唑的优异产率,并用作异