反应详情

To a stirred solution of the alcohol 20a (0.152 g, 0.71 mmol) in dichloromethane (5 ml) was added Dess-Martin periodinane (0.33 g, 0.78 mmol) at rt. The reaction was monitored by TLC (3:2 Hexane-ethyl acetate, UV-monitoring and staining using ammoniummolybdate-cerium sulfate in aq. 10% sulfuric acid). Staining indicates a fairly clean reaction, but UV monitoring indicates several byproducts). After 1 h the obtained yellow-red solution was diluted with dichloromethane (20 ml), then washed with 1:1 aq. 10% sodium thiosulfate/aq. saturated sodium hydrogen carbonate (3×20 ml), then dried (Na2SO4), filtered and concentrated. Flash chromatography of the residue using stepwise gradient elution (ethyl acetate in hexane 20-30%) followed by concentration of the appropriate fractions and drying the residue in vacuum overnight, gave the title compound as a colourless oil (0.054 g, 0.255 mmol, 36%).

1. customa fairly clean reaction, but UV monitoring
2. washwashed with 1:1 aq. 10% sodium thiosulfate/aq
3. dry with materialsaturated sodium hydrogen carbonate (3×20 ml), then dried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. washgradient elution (ethyl acetate in hexane 20-30%)
7. customdrying the residue in vacuum overnight