反应详情

A suspension of selenium dioxide (4.08 g, 37 mmol) in ethanol (35 mL) was refluxed for 10 minutes and then, Intermediate 65 (8.44 g, 37 mmol) was added. The mixture was refluxed overnight. The cooled reaction was filtered through Celite and the solvent removed under reduced pressure. The residue was diluted with methylene chloride (50 mL), washed with water (2×25 mL), dried (Na2SO4), and concentrated. Purification by column chromatography with silica gel using methylene chloride as eluent gave the title compound (4.12 g, 53%) as oil.

1. temperaturewas refluxed for 10 minutes
2. temperatureThe mixture was refluxed overnight
3. customThe cooled reaction
4. filtrationwas filtered through Celite
5. customthe solvent removed under reduced pressure
6. additionThe residue was diluted with methylene chloride (50 mL)
7. washwashed with water (2×25 mL)
8. dry with materialdried (Na2SO4)
9. concentrationconcentrated
10. customPurification by column chromatography with silica gel