Bis-(1H-imidazol-2-YL)-methanone → 5-Chloro-1,3-dihydro-6-nitro-2H-benzimidazol-2-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-chloro-5-nitro-benzene-1,2-diamine (8.34 g, 44.4 mmol) and THF (625 mL) was added carbonyl diimidazole (8.65 g, 53.3 mmol) at 0° C. The reaction mixture was allowed to warm to 23° C. and was stirred for 20 h at this temperature. The reaction mixture was concentrated to a volume of 300 mL and 500 mL aqueous 1M HCl was added, followed by water (total volume 2 L). The resulting suspension was cooled at 0° C. for 2 h, and the precipitate was collected and dried on the filter. It was then triturated with cold EtOAc (20 mL) and rinsed EtOAc (2×5 mL) to yield the titled compound (7.26 g, 76% yield). MS (ESI/CI): mass calcd. for C7H4ClN3O3, 213.0; m/z found, 214.0 [M+H]+.

Provenance & Evidence