Sulfamic Acid → 6-(Difluoromethoxy)[1]benzofuro[3,2-c]pyridine-9-carboxylic acid

Participants

Reaction Steps

To a well stirred solution of 6-(difluoromethoxy)[1]benzofuro[3,2-c]pyridine-9-carbaldehyde (500 mg, 1.90 mmol) in acetone (10 mL) was added sulphamic acid (276 mg, 2.85 mmol) at about 10° C. followed by drop wise addition of a solution of sodium chlorite (240 mg, 2.66 mmol) in water (5 mL) at about 0 to 5° C. The mixture was then stirred for about 1-2 hours. Ice cold water (50 mL) was added and the mixture was stirred for about 30 hours. The solid which separated was filtered, washed with water (3×5 mL) and dried at about 60-70° C. to give 6-(difluoromethoxy)[1]benzofuro[3,2-c]pyridine-9-carboxylic acid as a white solid.

Provenance & Evidence