SYNTHESIS OF 5-AZIDO-4-CYANOIMIDAZOLE AND ITS REACTION WITH ACTIVE METHYLENE-COMPOUNDS

Diazotisation of 1-acetamido-5-amino-4-cyanoimidazole 2 using sodium n itrite in aqueous acetic acid gave 5-azido-4-cyanoimidazole 3 in 94% y ield. Reaction of 3 with active methylene compounds R(1)COCH(2)R(2) [R (1) = Me, R(2) = COMe; R(1) = Me, R(2) = COPh; R(1) = Me, R(2) = COOEt ] or malononitrile in the presence of base led either to imidazo[5,1-d ][1,2,3,5]tetrazepines 6 and 8 or to imidazolyltriazoles 5, 7 and 9, d epending on the reaction conditions. Tetrazepine 6c evolves to triazol e 7c or 5c respectively in the presence of acid or by further treatmen t with base. Purine 10 was also isolated in the reaction of 3 with mal ononitrile.