2-Methyl-2-butene → 5-{4-[(1-acetylazetidin-3-yl)methoxy]phenyl}-6-chloro-1H-indole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a mixture of 5-{4-[(1-acetylazetidin-3-yl)methoxy]phenyl}-6-chloro-1H-indole-3-carbaldehyde (120 mg, 0.31 mmol) in acetonitrile (6 mL) and tert-butanol (6 mL) was added 2-methyl-2-butene (2.17 g, 31 mmol). The mixture was cooled to 0° C., and treated with a solution of sodium chlorite (418 mg, 6.2 mmol) and sodium phosphate monobasic hydrate (856 mg, 6.2 mmol) in water (6 mL). The reaction mixture was stirred at room temperature for 16 hours. A solution of sodium sulfite was added slowly to the reaction mixture, and stirred for 1 hour. The reaction mixture was partially evaporated in vacuo. The aqueous residue was extracted with ethyl acetate (10 mL×3). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo to give a brown residue. The residue was purified by preparative HPLC to give 5-{4-[(1-acetylazetidin-3-yl)methoxy]phenyl}-6-chloro-1H-indole-3-carboxylic acid (15 mg, 12%) as a white solid. MS (ES+) 399.0 (M+H)+. 1H NMR (400 MHz, CD3OD): δ 8.01 (m, 2H), 7.57 (s, 1H), 7.39 (d, 2H), 7.03 (d, 2H), 4.40 (m, 1H), 4.21 (m, 2H), 4.15 (m, 2H), 3.90 (m, 1H), 3.11 (m, 1H), 1.90 (s, 3H).

Provenance & Evidence