Facile synthesis of 5-bromotropono[c]-fused pyrazoles and isoxazole

摘要

A facile synthesis of a series of new 5-bromotropono[c]pyrazole derivatives (3 and 10-15) as well as 5-bromotropono[c]isoxazole (17) is described, involving a condensation reaction of 3-acetyl-5-bromotropolone (1) with hydrazine monohydrate (2), arylhydrazine hydrochlorides (4-9), and hydroxylamine hydrochloride (16), respectively. All the synthesized compounds were obtained in good yields of 56%-77% and their structures were characterized by spectral data and HRMS.