Triazines and related products. Part 27. Thermolysis of 4-anilino-1,2,3-benzotriazines

Abstract

Thermolysis of 4-(4-cyanoanilino)-1,2,3-benzotriazine (1a) in morpholine affords 3-[2-amino-N-(4-cyanophenyl)benzimidoyl]-4-(4-cyanophenylimino)-3,4-dihydro-1,2,3-benzotriazine (3a) in addition to the major product 2-amino-N²-(4-cyanophenyl)-N¹N¹-oxydiethylenebenzamidine (2a). The yield of (3a) increases if high boiling non-nucleophilic solvents are employed as the thermolysis medium. Decomposition of (3a) in hot acetic acid affords derivatives of 4-(4-cyanophenyl)-2-phenyl-quinazoline.