反应详情

To a solution of 6-nitrochromone (2.0 g, 10.5 mmol) in methanol/ethyl acetate (100 mL/20 mL) purged with argon, was added 5% Pd/C (Degussa-wet, 0.5 g) catalyst. Hydrogen gas was bubbled through the slurry with stirring until (2 hrs.) LCMS and TLC showed complete conversion of starting material to product. The spent palladium catalyst was filtered off through a celite, and the solid was washed with methanol. The combined filtrate and washings were evaporated to produce 6-amino-chromen-4-one (1.58 g, 94%) as a light yellow solid. LCMS m/z (%)=162 (M+H, 100), 1H NMR (400 MHz, CDCl3) δ: 7.79 (d, J=5.96 Hz, 1H), 7.38 (d, J=2.86 Hz, 1H), 7.29 (d, J=8.88 Hz, 1H), 7.01 (dd, J=8.80 Hz, 2.8 Hz, 1H), 6.26 (d, J=5.96 Hz, 1H), 5.29 (s, 2H).

1. customHydrogen gas was bubbled through the slurry
2. filtrationThe spent palladium catalyst was filtered off through a celite
3. washthe solid was washed with methanol
4. customThe combined filtrate and washings were evaporated