Sodium hydride → 4-chloro-1-(diphenylmethyl)-1H-indole-2,3-dione

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 4-chloroisatin (9.10 g, 50.0 mmol) in N,N-dimethylformamide (100 mL) was added sodium hydride (2.20 g, 55.0 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 1 h, followed by the addition of bromodiphenylmethane (14.80 g, 56.8 mmol). The mixture was stirred at ambient temperature for 20 h, diluted with ethyl acetate, washed with water and brine, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo. The residue was recrystallized from diethyl ether and hexanes to afford 4-chloro-1-(diphenylmethyl)-1H-indole-2,3-dione (14.20 g, 81%): 1H NMR (300 MHz, CDCl3) δ7.37-7.17 (m, 11H), 6.98-6.95 (m, 2H), 6.42 (d, J=9.0 Hz, 1H); MS (ES+) m/z 369.9 (M+23), 371.9 (M+1).

Provenance & Evidence