Water → 1-(diphenylmethyl)-4-fluoro-1H-indole-2,3-dione

Participants

Reaction Steps

To a solution of 1-(diphenylmethyl)-3-iodo-4-fluoroindole (8.85 g, 20.7 mmol) in a mixture of acetonitrile (25 mL) and water (5 mL) was added ruthenium (III) chloride monohydrate (0.30 g, 1.45 mmol) and sodium periodate (13.3 g, 62.2 mmol). The reaction mixture was stirred at ambient temperature for 16 h. The reaction mixture was diluted with ethyl acetate (100 mL), washed with water (3×25 mL), saturated aqueous ammonium chloride (3×25 mL) and brine (3×25 mL), dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The residue was crystallized from acetonitrile to afford 1-(diphenylmethyl)-4-fluoro-1H-indole-2,3-dione (1.73 g, 25%) as an orange solid: mp 168-171° C.; 1H NMR (300 MHz, DMSO-d6) δ 7.49-7.41 (m, 1H), 7.38-7.28 (m, 10H), 6.86 (dd, J=8.8, 8.8 Hz, 1H), 6.80 (s, 1H), 6.45 (d, J=8.1 Hz, 1H); 13C NMR (75 MHz, DMSO-d6) δ 178.3, 157.8, 157.7 (d, 1JC-F=261.0 Hz), 150.6 (d, 3JC-F=6.0 Hz), 139.7 (d, 2JC-F=10.0 Hz), 137.0, 128.5, 128.3, 127.8, 110.7 (d, 2JC-F=19.5 Hz), 108.8 (d, 4JC-F=2.9 Hz), 106.4 (d, 3JC-F=18.2 Hz), 28.7; MS (ES+) m/z 332.2 (M+23).

Provenance & Evidence