Water → 7-bromo-2-[(E)-2-(2-chlorophenyl)ethenyl]-5-methoxy-1-benzofuran

Participants

Reaction Conditions

Reaction Steps

To a solution of diethyl 2-chlorobenzylphosphonate (4.91 g, 0.018 mol) and 7-bromo-5-methoxybenzofuran-2-carbaldehyde (11.27 g, 0.016 mol) in tetrahydrofuran (80 mL) was added sodium hydride (60% dispersion in mineral oil, 0.74 g, 0.0185 mol). After 5 min. the reaction mixture was warmed to 60° C. for 1 h. The reaction mixture was cooled to room temperature, water (10 mL) was carefully added and the tetrahydrofuran was removed. Water (50 mL) was added and the mixture was extracted with ethyl acetate (3×100 mL). The combined ethyl acetate extracts were washed with brine (50 mL), dried over magnesium sulphate, filtered and concentrated to dryness. Trituration with diethyl ether (20 mL) gave solid material which was further washed with diethyl ether (20 ml). The liquors were concentrated and triturated with diethyl ether (10 mL), the solid being collected. The combined solids gave (859) (4.89 g, 84%). 1H NMR δ (CDCl3) 7.70 (d, J=16 Hz, 1H), 7.65 (dd, J=7.7, 1.5 Hz, 1H), 7.4 (dd, J=6.0, 1 Hz, 1H), 7.23 (m, 2H), 7.05 (d, J=2.3 Hz, 1H), 6.94 (d, J=16 Hz, 1H), 6.92 (d, J=2.3 Hz, 1H), 6.72 (s, 1H), 3.82 (s, 3H); MH+:364.9, 362.9 MH−:362.9, 360.9.

Provenance & Evidence