A New Regiospecific Synthesis of Isomeric 3(4)-Aryl-4(3)-nitro-1,2,5-oxadiazole 2-Oxides

New general, regiospecific methods of synthesis of isomeric 3(4)-aryl-4(3)-nitro-1,2,5-oxadiazole 2-oxides are suggested based on the cyclization of nitro-substituted a-nitrooximes; these methods involve the action of nitrosylating reagents on α-nitrostyrenes and 2-aryl-2-oximino-1,1-dinitroethanes, respectively.