Hydrochloric Acid → 7-Formyl-N-(2-methoxy-5-methylphenyl)-1-benzofuran-5-sulfonamide

Participants

Reaction Steps

Osmium tetroxide (84 mg, 0.33 mmol) was added to a solution of N-(2-methoxy-5-methylphenyl)-7-vinyl-1-benzofuran-5-sulfonamide (1.25 g, 3.3 mmol; Intermediate 61) and lutidine (0.71 g, 6.6 mmol) in dioxane (30 mL). A solution of sodium periodate (2.82 g, 13.2 mmol) in water (10 mL) was added under stirring. After 90 min, aqueous HCl (2 M; 40 mL) was added to give a clear solution. Addition of water (200 mL) gave a precipitate that was collected by filtration. This material was washed with water and dried to give 1.12 g (88%) of the title product. 1H NMR (400 MHz, CDCl3) δ 2.27 (s, 3H), 3.55 (s, 3H), 6.57 (d, 1H), 6.80-6.85 (m, 1H), 6.92 (d, 1H), 7.02 (br s, 1H), 7.38 (d, 1H), 7.85 (d, 1H), 8.22 (d, 1H), 8.28 (d, 1H), 10.38 (s, 1H).

Provenance & Evidence