反应详情

Methanol (25 mL) was vigorously stirred under nitrogen for 20 min and then 7-fluoroisatin (IIIa) (150 mg, 0.91 mmol) and 3-acetoxyindole (106 mg, 0.61 mmol) were added and stirring was Continued for 5 min. Anhydrous Na2CO3 (155 mg) was added and the stirring was continued for 3 h. The dark precipitate was filtered and washed with aqueous methanol (1:1, 20 mL) to give 7 (130 mg, 0.46 mmol, 77%) selectively in a Z form. 1H NMR (DMSO, 400 MHz, δ ppm, J in Hz) 11.37 (1H, s, N′—H), 11.12 (1H, s, N—H), 8.58 (1H, d, J=7.7 Hz, H-4), 7.64 (1H, d, J=7.5 Hz, H-4′), 7.57 (1H, t, J=7.5 Hz H-6′), 7.42 (1H, d, J=7.5 Hz, H-7′), 7.15 (1H, t, J=8.0 Hz, H-5), 7.02 (2H, m, H-5′, 6); CI-MS m/z 281 (M+H)+. Anal. (C16H9N2O2F) C, H, N.

1. waitthe stirring was continued for 3 h
2. filtrationThe dark precipitate was filtered
3. washwashed with aqueous methanol (1:1, 20 mL)