Trimethylsilyldiazomethane → Methyl 6-methyl-1-benzofuran-2-carboxylate

Participants

Reaction Steps

To a solution of 6-methylbenzofuran-2-carboxylic acid (11 g, 62.4 mmol) in 468 mL of toluene and 156 mL of MeOH was added 2N TMS-CHN2 (46.8 mL, 94 mmol) dropwise at room temperature. The reaction was stirred at room temperature for 6 hr. The reaction was then quenched by addition of acetic acid dropwise at 0° C. until the yellow color vanished, and gas evolution ceased. The reaction was concentrated under reduced pressure, and the residue was purified by silica gel flash chromatography, 100% Heptane-10% Ethyl Acetate/90% Heptane, to give methyl 6-methylbenzofuran-2-carboxylate (7.96 g). 1H NMR (400 MHz, DMSO-d6) δ 2.46 (s, 3H), 3.88 (s, 3H), 7.20 (dd, J=8.3, 1.0 Hz, 1H), 7.53 (s, 1H), 7.67 (d, J=8.1 Hz, 1H), 7.71 (d, J=1.0 Hz, 1H).

Provenance & Evidence