Synthesis of new heteroaromatic systems: Naphth[2,1-e]imidazo[5,1-c]-1,2,4-triazines and benz[e]imidazo-[5,1-c]-1,2,4-triazines

Cyclization of azo compounds, synthesized from 5-diazoimidazoles and 2-naphthol or p-substituted phenols, into naphth[2,1-e]imidazo[5,1-c]-1,2,4-triazines and benz[e]imidazo[5,1-c]-1,2,4-triazines occurs only in the presence of p-toluenesulfonic acid. Imidazo[4,5-d]-1,2,3-triazines are also formed in this reaction when an amide substituent is present in the imidazole ring.Ural State Technical University, Ekaterinburg 620002, Russia: e-mail: mokr@htf.ustu.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 540–546, April, 2000.