New investigations on the chemical behavior of 4-keto-1H-4,5-dihydro-1,2,5-benzotriazepines

Article abstract of DOI:10.1016/S0040-4020(01)97442-3

The chemical behavior of 4-keto-1H-4,5-dihydro-1,2,5-benzotriazepines towards basic reagents has been investigated. Evidence is given that 4-keto-1H-4,5-dihydro-1,2,5-benzotriazepines unsubstituted at position 3 are cleaved by sodium hydroxide and alkoxides furnishing sodium cyanide and 2-amino-3-keto-quinoxalines. The same benzotriazepines substituted by a carbamidoximo- or a carbohydrazino-group at position 3 undergo, when treated with the same reagents, isomerization reactions yielding 3-amino-4-arylazo-isoxazolin-5-ones and 4-arylazo-pyrazolidin-3,5-diones respectively. The structure of these products is demonstrated and a mechanism for their formation is proposed.