Abstract
Reactions of 2-imino-2H-cycloheptoxazoles with amines and hydrazines were examined. Reactions of 2-imino-2H-cycloheptoxazole derivatives with primary amines such as methylamine, benzylamine, and p-toluidine gave 1-substituted cycloheptimidazol-2(1H)-one derivatives (II : R=CH3, R=C6H5CH2, R=p-CH3C6H5). In the reaction with benzylamine, a trace of 2-benzylaminocycloheptimidazole (IV) and 1-benzyl-2-imino-1, 2-dihydrocycloheptimidazole (III) were obtained as by-products. Reaction of I with dimethylamine gave 2-dimethylaminocycloheptimidazole (XII) and cycloheptimidazol-2(1H)-one (XIII). Reaction with cyanamide gave 2-aminocycloheptimidazole (XIV). Hydrolyses of 4-bromo-(IIe) and 8-bromo-1-benzylcycloheptimidazol-2(1H)-one (IIg) gave 1-benzyl-(X) and 3-benzyl-cycloheptimidazole-2, 4(1H, 3H)-dione (XI), respectively. Reaciton of I with hydrazine hydrate, phenylhydrazine, m-nitrophenylhydrazine, and benzylhydrazine gave the corresponding 1-aminocycloheptimidazol-2 (1H)-one derivatives (XV, XVIII-XX) shown in Table I. Reaction of I with benzoylhydrazine, isonicotinoylhydrazine, and acetylhydrazine gave 2-ureidotropone acylhydrazones (XXII-XXIV), which were easily converted to 1-acylaminocycloheptimidazol-2 (1H)-ones (XXV-XXVII). Reaction of I with 2-hydrazinotropone gave 2-ureidotropone 2-troponylhydrazone (XXVIII).
