I2/TBHP promoted oxidative C–N bond formation at room temperature: Divergent access of 2-substituted benzimidazoles involving ring distortion
作者:Moumita Saha、Asish R. Das
DOI:10.1016/j.tetlet.2018.05.028
日期:2018.6
A new ‘one pot’ tandem synthesis of 2-substituted benzimidazoles has been developed from 2-aminobenzyl alcohol/2-aminobenzamide and different coupling partners (nitriles, aldehydes and 1,3-diketones) via iodine and TBHP promoted oxidative ring contraction. The present strategy involves sequential C–N bond formation, cyclization, subsequent ring contraction and dehydrogenation to afford various medicinally
由2-氨基苄醇/ 2-氨基苯甲酰胺和不同的偶合伴侣(腈,醛和1,3-二酮)通过碘和TBHP促进了氧化环收缩,开发了一种新的“一锅”串联合成2-取代的苯并咪唑类化合物。目前的策略包括连续的C–N键形成,环化,随后的环收缩和脱氢,以中等到良好的产率提供各种具有医学重要性的苯并咪唑衍生物。这种操作简单的合成方法是在室温下于无碱条件下进行的,广泛适用于带有氧化倾向性官能团的各种腈和醛,值得注意的是,各种无环的1,3-二酮经历了选择性的C–C键裂解反应在温和条件下生成2-烷基苯并咪唑。