4-(3,5-Dichlorophenyl)-1-(methoxycarbonyl)semicarbazide → 4-(3,5-Dichlorophenyl)-1,2,4-triazolidine-3,5-dione

Participants

Reaction Steps

A suspension of 4-(3,5-dichlorophenyl)-1-(methoxycarbonyl)semicarbazide (30.3 g, 109 mmol) (Preparation 2) in KOH (54.5 ml, 4M) was heated under reflux for 1 h. After cooling to RT, the insoluble material was discarded and the filtrate acidified to pH 1-2. The precipitate was filtered, washed with water and pentane, and oven dried to yield the above compound as a white solid (27 g, mp=260° C.). 1H NMR (DMSO-d6): 10.80 (2H, s), 7.66 (3H, m).

Provenance & Evidence