Cyclization of o-alkynylbenzaldehydes with o-diaminobenzenes in DMSO under the sequential action of NH4Br and K2CO3 affords 11-arylmethylidene-11H-isoindolo[2,1-a]-benzimidazoles as a result of 5-exo-dig ring closure; whereas replacement of treating with K2CO3 by heating at 110–115 °C results in 6-endo-dig cyclization with formation of 6-arylbenzimidazo[2,1-a]isoquinolines.

中文翻译：

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由邻炔基苯甲醛和邻二氨基苯选择性合成一锅11-芳基亚甲基-11 H-异吲哚并-[2,1-a]苯并咪唑和6-芳基苯并咪唑并[2,1-a]异喹啉

在NH4Br和K2CO3的顺序作用下，将邻炔基苯甲醛与邻二氨基苯在DMSO中环化，由于5-exo-dig环封闭，得到11-芳基亚甲基-11H-isoindolo [2,1-a]-苯并咪唑；而通过在110–115°C的加热条件下用K2CO3代替处理会导致6-内-挖-环化反应，形成6-芳基苯并咪唑并[2,1-a]异喹啉。