反应详情

To a stirred mixture of 2-[(4S)-2,2-dimethyl-1,3-dioxolan-4-yl]ethanol (50.89 g, 0.348 mol) and pyridine (113 ml, 1.39 mol) in dichloromethane (500 ml) was added gradually p-toluenesulfonyl chloride (79.65 g, 0.418 mmol) at ice-bath temperature. After removal of ice-bath, the reaction mixture was stirred at ambient temperature overnight. The mixture was poured into ice-cooled 1N-HCl (400 ml) and the mixture was extracted with dichloromethane. The organic layer was washed with saturated NaHCO3 solution and brine, dried with MgSO4, and concentrated in vacuo. The residue was purified by silica gel (800 g) column chromatography eluting with toluene/ethyl acetate (50:1 to 10:1) to give 2-((4S)-2,2-dimethyl-1,3-dioxolan-4-yl)ethyl p-toluenesulfonate (85.0 g, 81.3%) as an oil.

1. customAfter removal of ice-bath
2. additionThe mixture was poured into ice-
3. temperaturecooled 1N-HCl (400 ml)
4. extractionthe mixture was extracted with dichloromethane
5. washThe organic layer was washed with saturated NaHCO3 solution and brine
6. dry with materialdried with MgSO4
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel (800 g) column chromatography
9. washeluting with toluene/ethyl acetate (50:1 to 10:1)