Methyl propiolate → Methyl 2-methyl-1H-imidazole-5-carboxylate

Participants

Reaction Steps

A solution of N′-hydroxyethanimidamide (65 g, 880 mmol) in anhydrous methanol (2 L) was treated with methyl propiolate (100 g, 1.19 mol), and the reaction was heated at reflux for 4 hours. The reaction mixture was concentrated in vacuo, and the residue was diluted with diphenyl ether (1 L) and heated at reflux for 4 hours. The hot solution was filtered, and the filtrate was cooled to room temperature and diluted with hexanes (2 L). The resulting solid was washed with diethyl ether (1 L), to afford the product as a brown solid. Yield: 60 g, 430 mmol, 49%.

Provenance & Evidence