反应详情

温度

0 °C

To a solution of (2S, 4R, 5R)-5-amino-2-benzhydryl-tetrahydro-pyran-4-ol 31a (0.02 g, 0.09 mmol), 4-hydroxybenzaldehyde (0.01 g, 0.09 mmol) and glacial acetic acid (0.005 g, 0.09 mmol) in 1,2-dichloroethane (5 ml) was added portionwise NaCNBH3 (0.007 g, 0.11 mmol) in methanol (1 ml). The reaction was continued for 4 hr. Water was added to quench the reaction and the mixture was stirred for 30 minutes at 0° C. The reaction mixture was stirred with saturated aqueous NaHCO3 and the product was extracted with methylene chloride (3×10 ml). The combined organic phases were washed with brine, water and dried over anhydrous Na2SO4. Solvent was removed under reduced pressure, and the residue was purified by flash chromatography (Hexane/Ethyl Acetate/Triethylamine 3:2:0.2) to give (2S, 4R, 5R)-2-benzhydryl-5-(4-hydroxy-benzylamino)-tetrahydropyran-4-ol, (−)-32a, 0.03 g (80%, [α]D=(−)72.6, c=1, MeOH).

1. customto quench
2. customthe reaction
3. extractionthe product was extracted with methylene chloride (3×10 ml)
4. washThe combined organic phases were washed with brine, water
5. dry with materialdried over anhydrous Na2SO4
6. customSolvent was removed under reduced pressure
7. customthe residue was purified by flash chromatography (Hexane/Ethyl Acetate/Triethylamine 3:2:0.2)