反应详情

To a mixture of 4-chloro-1-(2-chlorophenyl)-2-oxo-1,2-dihydropyridine-3-carbonitrile obtained in Step D of Example (16.4 g) and N,N-dimethylformamide (124 mL) was added N-bromosuccinimide (16.5 g) at 60° C., and the mixture was stirred for 40 hr. The reaction mixture was cooled to room temperature, and poured into water. The resulting solid was collected by filtration, and washed with water to give the title compound (20.9 g).

1. filtrationThe resulting solid was collected by filtration
2. washwashed with water