Imidazole → 25700-00-9

Participants

Reaction Steps

A mixture of 25 g of 3'-bromoacetophenone, 9.0 g of imidazole, 18 g of anhydrous potassium carbonate, 1.0 g of copper oxide (CuO) and 30 ml of pyridine is refluxed for 64 hours. The mixture is cooled to room temperature, filtered and the filter cake washed with 50 ml of pyridine and 3×50 ml of dichloromethane. The combined filtrates are concentrated to dryness under vacuum. The residue is partitioned between 250 ml of dichloromethane and 150 ml of water. The emulsion is clarified by filtration through a pad of diatomaceous earth. The organic layer is separated, dried (MgSO4) and filtered through a pad of hydrous magnesium silicate. The pad is washed with 50 ml of dichloromethane and the combined filtrate is concentrated on a steam bath to 150 ml and while hot 300 ml of hexane is added. The mixture is cooled to room temperature, activated carbon added and the mixture filtered through diatomaceous earth. The filtrate is cooled to -10° C. and filtered to give 3.6 g of crystals, mp 69°-71° C. The filtrate is treated with activated carbon, filtered and the filtrate evaporated to give 12 g of crystals, mp 62°-65° C.

Provenance & Evidence