Potassium Acetate → Methyl 4-(acetyloxy)-2-methyl-1-benzofuran-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of E-3-methoxycarbonyl-4-(5-methylfur-2-yl)-but-3-enoic acid (Method 15; 1.39 g, 6.2 mmol) and potassium acetate (620 mg, 6.3 mmol) in acetic anhydride (12.5 ml) was heated at 140° C. for 15 mins. The reaction mixture was cooled and poured on to a water/ethyl acetate mixture; the aqueous layer was separated and the organic layer washed sequentially with saturated sodium bicarbonate solution and brine, dried (MgSO4) and evaporated in vacuo to yield the crude product as a dark crystalline mass. This was chromatographed (50 g Bondelut, eluting with hexane containing ethyl acetate, 0-100%) to give the title compound as a pale yellow solid, 1.42 g (92%). NMR: 2.36 (s, 3H), 3.34 (s, 3H), 3.87 (s, 3H), 6.68 (s, 1H), 7.56 (s, 1H), 7.96 (s, 1H); m/z 247 (M−H)−, 97.1% by LC-MS.

Provenance & Evidence