反应详情

Compound 7 (0.75 g, 2.66 mmol) was heated in a sealed tube with H2O (30 mL) at 200-220 0° C. for 2-3 h. On cooling, 2,7-difluoro-3,6-dihydroxyxanthone 8 precipitated out. The product was collected by filtration and washed with H2O to give 8 (0.58 g, 83%) as a light yellow solid. 1H NMR (300 MHz, DMSO-d6) δ 11.4 (s, 2H), 7.67 (d, 2H, J=10.9 Hz), 6.96 (d, 2H, J=7.1 Hz); 13C NMR (75 MHz, DMSO-d6) δ 173.1, 153.1, 152.0, 151.8, 150.4, 147.2, 112.6, 112.5, 111.1, 110.8, 104.7, 104.6; 19F NMR (282 MHz, DMSO-d6) δ −139.0 (dd, 2F); mass spectrum, calculated for C13H6F2O4 (MH+) 265.0, Found 264.9.

1. temperatureOn cooling
2. custom2,7-difluoro-3,6-dihydroxyxanthone 8 precipitated out
3. filtrationThe product was collected by filtration
4. washwashed with H2O