Synthesis of 2-aryl-6-nitro-4-(vic-triazol-1-yl)-1H-indoles from E-2,4,6-trinitrostilbenes

A method is developed for the preparation of 4-(vic-triazol-1-yl)indoles that involves replacement of the ortho-NO2 group in E-2,4,6-trinitrostilbenes by an azido group, condensation of E-2-azido-4,6-dinitrostilbenes with acetylacetone, replacement of the second ortho-NO2 group in the resulting stilbenes by N3, and subsequent thermolysis of the azide into the target indole. The reactions of E-2-azido-4,6-dinitrostilbenes with cyclohexane-1,3-dione gave E-2-amino-4,6-dinitrostilbenes, which can be used for selective transformation of the ortho-NO2 group into an amino group in E-2,4,6-trinitrostilbenes.