Hydrochloric Acid → 5-Chloro-2-cyclopropyl-1,6-dihydro-6-oxo-4-pyrimidinecarboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-cyclopropyl-1,6-dihydro-6-oxo-4-pyrimidinecarboxylic acid (i.e. the product of Step A1 or A2) (184 g, 1.02 mol) in water (45 mL) and concentrated hydrochloric acid (292 g, 3 mol) at 8-12° C. was added dropwise aqueous sodium hypochlorite solution (8.4%, 1.02 kg, 1.15 mol) over 2 h so that with cooling the reaction mixture was maintained at 8-10° C. The mixture was then held at 10-12° C. for 1 h and the conversion was monitored by HPLC. When less than 5% of the starting material remained solid sodium bisulfite was added until a negative KI starch paper test was obtained. The mixture was cooled to 5° C., and the suspended product was isolated by filtration and washed with a minimum amount of cold water. The product was then dried to constant weight in vacuum-oven at 50° C. to afford the title compound (194 g); m.p. 189-190° C.

Provenance & Evidence