Ammonium formate → 4-Bromo-1H-benzimidazole

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3-bromo-2-nitrobenzenamine (4.7 g, 21.66 mmol) in formic acid (98%, 50 mL) was added 10% Pd/C and ammonium formate (13.6 g, 216.6 mmol) and the reaction mixture was stirred under nitrogen at 120° C. for 24 h. The catalyst was filtered, the filtrate was concentrated, the residue was dissolved in water (100 mL) and extracted with EtOAc (2×150 mL). The combined organic extracts were washed with water and brine, dried (Na2SO4), filtered and concentrated in vacuo to afford 1.3 g (30%) of crude 4-bromo-1H-benzo[d]imidazole (52) as dark brown solid: MS (ESI) m/z=197.1 [M+1]+.

Provenance & Evidence