Hydrochloric Acid → 3-Methyl-4-methoxy-7-(2-thienoyl)benzofuran

Participants

Reaction Conditions

Reaction Steps

An intimate mixture of compound 2 (3.50 g, 11.0 mmol), quinoline (7 mL), and copper powder (0.70 g, 11.0 mol) was carefully heated to 210° C. and maintained at that temperature until gas evolution ceased (about 10 minutes). The resulting mixture was cooled to 80° C. and poured into 1N HCl (120 mL). Chloroform (50 mL) was added and the mixture stirred for 5 minutes and filtered through a pad of celite. The pad was washed with an additional portion of chloroform (25 mL). The organic layer was separated and the aqueous layer extracted with additional portions of chloroform (2×50 mL). The combined organic extracts were dried (Na2SO4) and concentrated. The crude product was purified by preparative HPLC using 15% ethyl acetate in hexane as eluant to afford 3-methyl-4-methoxy-7-(2-thienoyl)benzofuran. mp 131°-134° C.; 1H NMR d 2.40 (3H, d, J=1 Hz), 4.02 (3H, s), 6.71 (1H, d, J=8 Hz), 7.17 (1H, m), 7.38 (1H, d, J=1 Hz), 7.70 (3H, m).

Provenance & Evidence