Bromide ion → 1-(2,4-Dichlorophenyl)-2-(1H-imidazol-1-yl)ethan-1-one

Participants

Reaction Steps

A 300 ml solution of diethyl ether containing 100 g (0.53 mole) of 2,4-dichloroacetophenone was cooled to 0°-5° C., and treated with 85.0 g (0.53 mole) of bromide and stirred one hour. The organic layer was washed with 3×500 ml portions of saturated sodium bicarbonate solution followed by 3×500 ml portions of water. The aqueous layer was removed and the organic layer treated with a 200 ml portion of methanol containing 108.0 g (1.6 mole) of imidazole and stirred in the cold overnight. The solution was concentrated, poured into 1600 ml of H2O with separation of an oil, the aqueous layer decanted, and the oil extracted 2×300 ml of methylene chloride. The combined organic phase was washed 2×300 ml of H2O, dried over magnesium sulfate and concentrated to give 108.8 g (80%) of a red oil. The nitrate salt was formed by treatment of the oil in acetone/ether solution with excess nitric acid, m.p. 161°-163° C. The free base obtained by neutralization was recrystallized from ethanol/water, m.p. 80°-82° C.

Provenance & Evidence