Ammonia → 2,4-Dichloropyrimidine-5-carboxamide

Participants

Reaction Steps

A solution of ammonia (14 g) in 1,4-dioxane (500 ml) was added drop-wise to an ice-cooled stirred solution of 2,4-dichloro-5-pyrimidinecarbonyl chloride (78 g, crude) in 1,4-dioxane (400 ml) under nitrogen. The ice-bath was removed and the solution was stirred for 30 min and concentrated. The solid residue was partitioned between ethyl acetate (500 ml) and saturated aqueous sodium bicarbonate (500 ml), the organic washed with saturated aqueous sodium bicarbonate (500 ml, ×2), followed by brine (300 ml). The organic phase was dried (sodium sulphate) and concentrated to give a yellow solid. To the residue was added diethyl ether (50 ml) and the resulting suspension was treated under ultrasonic wave for 8 min then filtered. The residue was washed with ethyl ether (50 ml) to give the title compound as a white solid (30 g).

Provenance & Evidence