Semicarbazide hydrochloride → 6-(4-Fluorophenyl)-1,2,4-triazin-3(2H)-one

Participants

Reaction Steps

A mixture of 2,2-diethoxy-1-(4-fluorophenyl)ethanone (5.2 g, 23 mmol), semicarbazide hydrochloride (2.6 g, 24 mmol) in ethanol (50 mL) was stirred overnight at ambient temperature and then heated to 80° C. for 5 hours. The reaction mixture was concentrated and the resulting residue was dissolved in acetic acid (50 mL) which was heated to 130° C. for 6 h. After cooling, the mixture was concentrated under reduced pressure. The residue was triturated with ethyl ether, filtered, and washed with diethyl ether and then hexanes. The crystalline material was collected and dried under high vacuum to give the desired product. (4.2 g, 96%) LCMS: (M+H)=192.1.

Provenance & Evidence