Formaldehyde → 2-Hydroxy-3-(trifluoromethoxy)benzaldehyde

Participants

Reaction Steps

A solution of 2-trifluoromethoxyphenol (5.13 g, 28.8 mmol) in anhydrous acetonitrile (150 mL) in oven-dried glassware was treated with triethylamine (15.0 mL, 108 mmol) and MgCl2 (4.11 g, 43.2 mmol) which had been dried under vacuum with heat. Paraformaldehyde (5.18 g, 172 mmol), which had been dried under vacuum with P2O5, was added and the solution was heated to reflux. After 5 days, the reaction was quenched with 1 N HCl (200 mL) and the mixture was extracted using Et2O (2×100 mL). The combined organics were washed with brine (2×150 mL), dried (Na2SO4) and concentrated to a yellow solid. Purification by column chromatography (silica gel, 98:2 to 95:5 hexanes/EtOAc) gave the title compound (2.45 g, 41%) as a yellow powder: 1H NMR (300 MHz, DMSO-d6) δ 10.24 (s, 1H), 7.75-7.65 (m, 2H), 7.08 (t, J=7.9 Hz, 1H).

Provenance & Evidence