反应详情

Dissolve 3-hydroxybenzaldehyde (18.4 g, 15.07 mmol) in tetrahydrofuran (100 mL). Add nitromethane ((42 mL, 780 mmol), cool in an ice bath and add tetrabutylammonium fluoride (151 mL, 151 mmol, 1.0 M in tetrahydrofuran). Stir for 2 hours, dilute with ethyl acetate (200 mL), wash with water (3×500 mL) and saturated aqueous sodium chloride (200 mL). Extract the aqueous washes with diethyl ether (3×), wash with saturated aqueous sodium chloride, dry (magnesium sulfate), filter through a pad of silica gel, and concentrate. Suspend the residue in hot dichloromethane with 5% ethyl acetate, cool and filter solid. Purify filtrate using silica gel chromatography, eluting with 5:95 ethyl acetate:dichloromethane. Combine the solid from the dichloromethane tritutation with the purified filtrate to give the desired compound (24.88 g, 90% total yield).

1. washwash with water (3×500 mL) and saturated aqueous sodium chloride (200 mL)
2. extractionExtract the aqueous washes with diethyl ether (3×)
3. washwash with saturated aqueous sodium chloride
4. dry with materialdry (magnesium sulfate)
5. filtrationfilter through a pad of silica gel
6. concentrationconcentrate
7. temperaturecool
8. filtrationfilter solid
9. washeluting with 5:95 ethyl acetate