A novel annulation reaction of N-substituted-2-nitrosoanilines with esters of α-isocyano acids. A one-pot, two-step route to 2-benzimidazole-substituted esters of α-amino acids
作者:Robert Bujok、Piotr Cmoch、Zbigniew Wróbel
DOI:10.1016/j.tetlet.2014.04.030
日期:2014.6
e derivatives, which, after reduction with Zn in AcOH produce 1-N-aryl-2-alkylaminobenzimidazoles. This two-step annulation proceeds efficiently in a one-pot protocol with isocyanides derived from esters of α-amino acids. The chirality of the latter remains unaffected in the reaction.
BF 3促进的异氰酸酯到N-芳基-2-亚硝基苯胺的两个氮原子上的α-加成反应生成3- N-羟基-(2-烷基亚氨基)苯并咪唑衍生物的稳定BF 3-络合物,在用Zn还原后在AcOH中生成1 - N-芳基-2-烷基氨基苯并咪唑。使用从α-氨基酸的酯衍生的异氰化物,一锅操作即可有效地进行这一两步环化。后者的手性在反应中不受影响。