Hydrochloric Acid → 6-Fluoro-2,3-dihydroxybenzaldehyde

Participants

Reaction Steps

To a cold (−78° C.) solution of 6-fluoro-2,3-dimethoxy-benzaldehyde (4.50 g, 24.43 mmol) in anhydrous dichloromethane (30 mL) was added BBr3 (1M in DCM, 48.8 mL, 48.87 mmol) dropwise (duration 30 min). The reaction was warmed to room temperature and stirred for 4 h. Again cooled it to −78° C. and added 2N HCl (60 mL) to it dropwise. The reaction was stirred for overnight at room temperature and extracted with DCM. Combined organic layers were washed with water, sat. NaHCO3 solution, brine and dried over MgSO4. Filtration and removal of solvent provided 2.42 g (15.50 mmol, 64%) of the title compound as a yellow solid. This was used in the next step without further purification. 1H NMR (400 MHz, DMSO-d6) δ ppm 10.22 (s, 1H), 7.04 (dd, J=8.6, 5.5 Hz, 1H), 6.61 (dd, J=10.4, 8.8 Hz, 1H); 19F NMR (376 MHz, DMSO-d6) δ ppm −131.69-−131.65 (m, 1F).

Provenance & Evidence