Unusual oxidation of 4-amino-4H,8H-bisfurazano[3,4-b:3’,4’-e]pyrazines

The oxidation of 4,8-diamino-4H,8H-bisfurazano[3,4-b:3’,4’-e]pyrazine 1 with positive halogen reagents and related oxidants afforded a stable nitrogen-centered radical, bisfurazano[3,4-b:3’,4’-e]pyrazine biradical 4; tetrazene 2 was a probable intermediate