Studies with 2-arylhydrazononitriles: Further investigations on reactivity of 2-arylhydrazononitriles towards hydroxylamine

摘要

The utilization of arylhydrazononitriles (6-9) for synthesis of azoles is demonstrated. Thus, arylazomalononitriles (6) reacted with hydroxylamine hydrochloride to afford isoxazol-5-imine (10), amidoxime (12) and bis-amidoxime (13) derivatives depending upon both the reaction conditions and molar ratio employed. 2-Thiazolyl-2-arylhydrazononitriles (7) and cyanoformazans (8) gave 1,2,3-triazole derivatives (15) and (17) respectively upon treatment with hydroxylamine hydrochloride and concomitant loss of water molecule. Formation of novel 1,2,4-triazin-5(4H)-one derivatives (21) has efficiently been carried out by treatment of amidoximes (18) with acetic anhydride in acetic acid.