Acetic Acid → 2-Bromo-3-(but-2-ynyl)-3,5-dihydro-imidazo[4,5-d]pyridazin-4-one

Participants

Reaction Conditions

Reaction Steps

6.31 ml (0.126 mol) hydrazine hydrate were added drop-wise at ambient temperature to a solution of 35.0 g (0.117 mol) ethyl 2-bromo-3-(but-2-ynyl)-5-formyl-3H-imidazole-4-carboxylate in 400 ml of ethanol. After 30 min stirring 27 ml (0.472 mol) concentrated acetic acid were added and the solution was then stirred for 1 h at 100° C. After cooling the precipitated solid was suction filtered, washed with ethanol and diethyl ether and dried. The solid was further purified by re-crystallization from EtOH.

Provenance & Evidence