反应详情

A solution of 21-bromo-3α-hydroxy-5β-pregnan-20-one (500 mg, 1.26 mmol), 4-hydroxypyridine (144 mg, 1.51 mmol), and triethyl amine (200 μL) in 10 mL of THF was heated under reflux for 4 h. The mixture was cooled to room temperature and partitioned between EtOAc and water. The organic layer was washed with sat. aq. NaCl, dried with MgSO4 and concentrated in vacua. The crude residue was subjected to flash column chromatography. Elution with 50% acetone in CH2Cl2 yielded 3α-hydroxy-21-(pyrid-4-yloxy)-5β-pregnan-20-one (40 mg) as an oily solid; TLC Rf (acetone:CH2Cl2 1:1)=0.28.

1. temperatureunder reflux for 4 h
2. custompartitioned between EtOAc and water
3. washThe organic layer was washed with sat. aq. NaCl
4. dry with materialdried with MgSO4
5. concentrationconcentrated in vacua
6. washElution with 50% acetone in CH2Cl2