Benzo[1,2‐ c :3,4‐ c ']bis[1,2,5]selenadiazole, [1,2,5]selenadiazolo‐[3,4‐ e ]‐2,1,3‐benzothiadiazole, furazanobenzo‐2,1,3‐thiadiazole, furazanobenzo‐2,1,3‐selenadiazole and related heterocyclic systems

The first synthesis of benzo[1,2‐ c :3,4‐ c ']bis[1,2,5]selenadiazole has been developed starting from commercially available 4‐nitrobenzo‐2,1,3‐selenadiazole. Improved syntheses of the related heterocycles [1,2,5]selenadiazolo[3,4‐ e ]‐2,1,3‐benzothiadiazole, furazanobenzo‐2,1,3‐thiadiazole and furazanobenzo‐2,1,3‐selenadiazole are also reported.