反应详情

A mixture of 1-(diphenylmethyl)-3-hydroxy-3-(5-hydroxy-2,1,3-benzoxadiazol-4-yl)-1,3-dihydro-2H-indol-2-one (21.8 g, 48.5 mmol), triethylsilane (50 mL) and trifluoroacetic acid (100 mL) was stirred at ambient temperature for 16 h, then heated to 45° C. for 1.5 h. The mixture was allowed to cool to ambient temperature and concentrated in vacuo. The residue was triturated with diethyl ether to afford 1-(diphenylmethyl)-3-(5-hydroxy-2,1,3-benzoxadiazol-4-yl)-1,3-dihydro-2H-indol-2-one (10.94 g, 52%) as a colorless solid: 1H NMR (300 MHz, CDCl3) δ10.90-10.00 (br s, 1H), 7.61-7.31 (m, 10H), 7.18 (s, 1H), 7.06-6.89 (m, 4H), 6.55 (d, J=8.4 Hz, 1H), 6.45 (d, J=9.6 Hz, 1H), 5.57 (s, 1H); MS (ES+) m/z 456.0 (M+23).

1. temperatureheated to 45° C. for 1.5 h
2. temperatureto cool to ambient temperature
3. concentrationconcentrated in vacuo
4. customThe residue was triturated with diethyl ether