反应详情

温度

45 °C

2-Hydroxy-4-nitro-benzoyl chloride (0.82 g, 4.07 mmol) in THF (15 mL) was added portionwise to a solution of 4-hydroxytetrahydropyran (0.8 mL, 8.1 mmol) in pyridine (4 μL) at 0° C., followed by a catalytic amount of 4-(dimethylamino)-pyridine (DMAP). The mixture was maintained overnight at 40-50° C. then diluted with water and extracted with ethyl acetate. The organic extract was washed successively with saturated sodium bicarbonate solution, water and brine solution, dried and concentrated to give a residue which was triturated with a mixture of DCM and petroleum ether. The residue was purified by flash column chromatography on silica, eluting with ethyl acetate/petroleum ether (2-15%) to give 2-hydroxy-4-nitro-benzoic acid tetrahydro-pyran-4-yl ester (0.32 g, 29%).

1. extractionextracted with ethyl acetate
2. extractionThe organic extract
3. washwas washed successively with saturated sodium bicarbonate solution, water and brine solution
4. customdried
5. concentrationconcentrated
6. customto give a residue which
7. customwas triturated with a mixture of DCM and petroleum ether
8. customThe residue was purified by flash column chromatography on silica
9. washeluting with ethyl acetate/petroleum ether (2-15%)