Ammonia → HCID 178513614, compound

Participants

Reaction Steps

2-Phenylbenzimidazole-4-carboxylic acid (50 mg, 0.21 mmol) was dissolved in dry tetrahydrofuran (10 ml) and thionyl chloride (16.8 μl, 0.231 mmol) and DMF (0.05 ml) were added. The mixture was stirred at room temperature for 12 hours, when a white precipitate developed, and the suspension was added dropwise to stirred aqueous ammonia (10 ml) over 10 minutes. The mixture was stirred for a further 30 minutes, diluted with water (20 ml), and neutralised with hydrochloric acid (4M). The white solid which was precipitated upon cooling, was collected by filtration to afford 2-phenylbenzimidazole-4-carboxamide (31 mg, 62%); vmax/cm−1 3320, 3180, 1660 and 1600; δH (d6-DMSO, 200 MHz) 7.45 (1H, t, Ar-5H), 7.72 (3H, d, 3-Ph-4H), 7.87 (1H, d, Ar-4H), 7.97 (1H, br s, CONH), 7.99 (2H, d, Ar-6H), 8.38 (2H, d, Ph-2-H and Ph-2-H); 9.5 (1H, br s, CONH); m/z (EI) 237 (M+), 220, 192, 165, 77.

Provenance & Evidence