Tetrahydrofuran → 3-(6-Bromo-1H-indol-3-yl)-4-(1-methy-1H-indol-7-yl)-pyrrole-2,5-dione

Participants

Reaction Conditions

Reaction Steps

To solution of 2-(1-methyl-1H-indol-7-yl)-acetamide (0.300 g, 1.59 mmol) in DMF (15 mL) was added a 1.0 M solution of potassium tert-butoxide in THF (1.59 mL, 1.59 mmol), followed after 5 minutes by (6-bromo-1H-indol-3-yl)-oxo-acetic acid methyl ester (0.235 g, 0.83 mmol) in DMF (1.25 mL). After another 5 minutes additional potassium tert-butoxide (1.59 mL) was introduced followed by the additional (6-bromo-1H-indol-3-yl)-oxo-acetic acid methyl ester (0.235 g, 0.83 mmol) in DMF (1.25 mL). The reaction was stirred for 5 minutes and an additional potassium tert-butoxide (1.59 mL) was introduced. After heating at 50° C. over night, then deep red solution and was cooled to room temperature, quenched with 1N HCl and poured in EtOAc. The two layers were separated and the organic layer was washed with H2O, saturated aq NaHCO3, and brine (×3), dried (MgSO4), filtered, and concentrated. Flash chromatography (80% EtOAc/hexane) gave the title compound (0.256 g, 38%) as a red solid. 1H NMR (400 MHz, DMSO-d6) 3.64 (s, 3H), 6.26 (d, J=4.4 Hz, 1H), 6.47 (d, J=2.8 Hz, 1H), 6.60 (dd, J=2, 8.8 Hz, 1H), 6.88 (d, J=7.2 Hz, 1H), 6.98 (dd, J=7.2, 7.2 Hz, 1H), 7.24 (d, J=3.6 Hz, 1H), 7.61 (dd, J=1.2, 8 Hz, 1H), 7.87 (d, J=2.8 Hz, 1H), 11.18 (s, 1H), 11.91 (s, 1H). MS (electrospray, m/z) 420/418 (M−−1).

Provenance & Evidence