Nitric Acid → 2-Amino-6-chloro-5-nitro-3,4-dihydropyrimidin-4-one

Participants

Reaction Steps

Following the method of O'Brien and Cheng (J. Med. Chem. 1966, 9, 573), to a stirred solution of 10.0 g (61.1 mmol) 2-amino-6-chloro-4-pyrimidinol monohydrate in 46 ml 98% sulfuric acid was added dropwise 9 ml 65% nitric acid at a rate such that the reaction temperature remainded around 40° C. After the addition was complete, stirring was continued for 1 hour at room temperature. The reaction mixture was then poured onto 150 ml ice-water and the resulting crystals were collected by filtration and washed sequentially with water, ethanol and ether to afford 12.6 g (99%) 2-amino-6-chloro-5-nitro-3H-pyrimidin-4-one as a light yellow crystalline solid. ES-MS m/e (%): 191 (M+H+, 100).

Provenance & Evidence