Potassium Hydroxide → 3-Acetylamino-2-benzoyl-6-chloroindole

Participants

Reaction Steps

To a solution of 3-acetylamino-2-benzoyl-6-chloro-1-(ethoxycarbonyl)indole (556 mg, 1.4 mmol) in ethanol/water (3:1, 20 ml) was added KOH (85% pellets, 480 mg, 7.2 mmol) and the mixture was heated at reflux temperature for 1 h. The mixture was cooled and concentrated, and the residue partitioned between water (50 ml) and diethyl ether (100 ml). The organic extract was washed with water (100 ml) and then brine (100 ml). After drying (MgSO4) and removal of solvent, the crude product was recrystallized from dichloromethane/hexane to afford 180 mg (41%) of the title compound as a yellow powder. m.p.: 212-213° C. 1H-NMR (CDCl3) δ: 9.90 (1H, br s), 8.29-8.15 (2H, m), 7.84-7.75 (2H, m), 7.70-7.52 (3H, m), 7.32-7.27 (1H, m), 7.12 (1H, dd, J=1.83, 9.16 Hz), 2.26 (3H, s). IR (KBr) ν: 3400, 1680, 1640, 1520, 1320 cm−1

Provenance & Evidence