I<sub>2</sub>-Mediated Intramolecular C–H Amidation for the Synthesis of N-Substituted Benzimidazoles
作者:Zhiyuan Hu、Ting Zhao、Manman Wang、Jie Wu、Wenquan Yu、Junbiao Chang
DOI:10.1021/acs.joc.7b00142
日期:2017.3.17
practical intramolecular C–H amidation methodology has been developed using molecular iodine under basic conditions. The required imine substrates were readily obtained by condensation of simple o-phenylenediamine derivatives and aldehydes. The transition-metal-free cyclization reaction described here works well with crude imines and allows for the sequential synthesis of N-protected benzimidazoles
在基本条件下,使用分子碘已开发出一种实用的分子内C–H酰胺化方法。通过简单的邻苯二胺衍生物和醛的缩合可以容易地获得所需的亚胺底物。本文所述的无过渡金属的环化反应可与粗亚胺很好地配合,无需分离较不稳定的缩合中间体,即可连续合成N-保护的苯并咪唑。这种操作简单的合成方法广泛适用于各种芳族,脂肪族和肉桂醛,以有效和可扩展的方式生产各种1,2-二取代的苯并咪唑衍生物。