4-a]benzimidazol-4(5H)-ones were obtained in five steps involving C-acylation of benzimidazole, its N-alkylation with ethyl bromoacetate, the ester hydrolysis, condensation with BocNHNH2, and the acid-catalyzed heterocyclization of thus obtained 2-(2-aroyl-1H-benzimidazol-1-yl)-N′-(tert-butoxycarbonyl)acetohydrazides. The geometry of tert-butyl carbazate rotamers was estimated with quantum chemical
在五个步骤中获得了3H- [1,2,5]三唑并[5,4-a]
苯并咪唑-4(5H)-,这些步骤涉及
苯并咪唑的C-酰化,
溴乙酸乙酯的N-烷基化,酯
水解,缩合。用BocNHNH 2,并由此酸催化2-(2-芳酰基-1H-
苯并咪唑-1-基)-N′-(叔丁氧基羰基)乙酰
肼。
氨基甲酸叔丁酯旋转异构体的几何形状是通过量子
化学计算来估计的。