Formic Acid → 2-(6,7-difluoro-1H-benzimidazol-1-yl)ethanol

Participants

Reaction Steps

A solution of 2-[(6-amino-2,3-difluorophenyl)amino]ethanol in 100 ml of formic acid is heated at 100° C. for 2 hours. The reaction is concentrated to dryness, taken into 100 ml of 2 N NH3 in ethanol and stirred for 2.5 hrs. The reaction is concentrated and taken into ethyl acetate. The resulting precipitate is collected by filtration and rinsed with cold ethyl acetate. The mother liquor is concentrated and purified by silica gel flash chromatography using ethyl acetate/heptane. The combined yield is 3.2 g or 93% for two steps based on 3.8 g of 2-[(2,3-difluoro-6-nitrophenyl)amino]ethanol.

Provenance & Evidence