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 no starting material. 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 as a light yellow solid (1.58 g, 94%). LCMS m/z (%)=162 (M+H, 100), 1H NMR (400 MHz, CDCl3) δ: 7.79-7.81 (d, J=5.96 Hz, 1H), 7.38 (d, J=2.86 Hz, 1H), 7.29-7.31 (d, J=8.88 Hz, 1H), 7.01-7.04 (dd, J=8.80, 2.8 Hz, 1H), 6.26-6.28 (d, J=5.96 Hz, 1H), 5.299 (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