反应详情

温度

-78 °C

NaCNBH3 (0.75 g, 12 mmol) was added portionwise to a mixture of 2-diphenylmethyl-2,3-dihydro-4H-pyran-4-one 2 (1.05 g, 4 mmol) and boron trifluoride etherate (1.99 g, 14 mmol) in dry THF (50 ml) cooled to −78° C. The reaction mixture was allowed to reach room temperature and the reaction was quenched with saturated aqueous NaHCO3 (30 ml). The organic phase was separated, and the aqueous phase was extracted with ethyl ether (3×20 ml). The organic phases were combined and dried over anhydrous Na2SO4. Removal of the solvent under reduced pressure, and purification by flash chromatography (hexane/ethyl acetate 7:3) first afforded trans-2-benzhydryl-tetrahydropyran-4-ol 3a (0.73 g, 68% yield).

1. customto reach room temperature
2. customthe reaction was quenched with saturated aqueous NaHCO3 (30 ml)
3. customThe organic phase was separated
4. extractionthe aqueous phase was extracted with ethyl ether (3×20 ml)
5. dry with materialdried over anhydrous Na2SO4
6. customRemoval of the solvent