Triethylamine → 7-Methoxybenzofuran-3-yl trifluoromethanesulfonate

Participants

Reaction Conditions

Reaction Steps

Trifluoromethanesulfonic anhydride (4.6 g, 16.3 mmol) was added dropwise to a solution of 7-methoxybenzofuran-3(2H)-one (1.8 g, 10.9 mmol), triethylamine (2.2 g, 21.8 mmol), and dichloromethane (40 mL) at −20° C. The resulting mixture was stirred at −20° C. for 2 h. The reaction mixture was neutralized with saturated aqueous NaHCO3 (22 mL). The organic layer was separated, washed with water (40 mL) and brine (40 mL), dried over Na2SO4, and concentrated in vacuo. The residue was purified on a silica gel column using petroleum ether to afford the title compound as yellow oil (2.3 g, yield 71%). 1H NMR (DMSO-d6, 400 MHz): δ 8.67 (s, 1H), 7.36 (t, 1H), 7.21 (d, 1H), 7.20 (d, 1H), 3.96 (s, 3H).

Provenance & Evidence