Ethanol → 7-(benzyloxy)-5-bromo-1-methyl-1H-benzo[d]imidazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-(benzyloxy)-4-bromo-N-methyl-6-nitroaniline 2.50 (770 mg, 2.25 mmol) in ethanol (12 mL) and formic acid (15 mL) was added iron (630 mg, 11.27 mmol) and heated at 90° C. at 4 h and LCMS shows still lot of starting material present. 500 mg of iron was added and the mixture was heated at 90° C. overnight. The reaction mixture was concentrated, diluted with water and acidified to pH˜7 with sat'd NaHCO3 and then the aqueous layer was extracted with EtOAc (3×). Combined organic layer were then washed successively with water and brine and dried over anhydrous magnesium sulfate. The residue was purified by flash column chromatography (SiO2, 100% EtOAc) to give 7-(benzyloxy)-5-bromo-1-methyl-1H-benzo[d]imidazole 2.51.

Provenance & Evidence