反应详情

To a room temperature solution of 3-hydroxypyridine (7.55 g, 0.0778 mol) in dimethylformamide (400 ml) was added in portions 3.74 g (0.0780 mol) of 50% sodium hydride. The mixture was stirred at room temperature for 30 minutes, followed by the addition of 20.0 g (0.0778 mol) of 3-bromo-6-methoxy-4-chromanone all at once. The resulting red-orange mixture was stirred at room temperature for 1 hour, after which tlc (20% ethyl acetate/CH2Cl2) indicated complete conversion of starting material to the more polar products. The reaction mixture was poured into 1.2 liter of H2O, adjusted to pH 8-9 with 1N NaOH and extracted with ethyl acetate (2×800 ml). The combined extracts were washed with H2O and brine, dried over Na2SO4, and concentrated in vacuo to a yellow oil. Purification by flash column chromatography using 2.3 Kg of fine mesh silica gel and eluting with 20% ethyl acetate/CH 2 Cl2 afforded title product as a pale yellow solid in 3.6% yield, m.p. 135°-136° C.

1. stirringThe resulting red-orange mixture was stirred at room temperature for 1 hour
2. extractionextracted with ethyl acetate (2×800 ml)
3. washThe combined extracts were washed with H2O and brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated in vacuo to a yellow oil
6. customPurification by flash column chromatography
7. washeluting with 20% ethyl acetate/CH 2 Cl2