Reactions of 2,3-dihydrospiro[1<i>H</i>-4- and 5-azabenzimidazole-2,1′-cyclohexane] with nucleophiles: A potential route to some substituted aromatic heterocycles
results in loss of the Br-atom presumably by an AEa-mechanism. Reduction of the substituted azaisobenzimidazoles with sodium hydrosulfite followed by fission of the cyclohexane ring leads to substituted o-diaminopyridines. They were cyclised in situ with various condens ing agents to give new heterocyclic systems. Equimolar mixtures of some azaisobenzimidazoles and dihydroazabenzimidazoles lead to the