反应详情

温度

60 °C

To 200 ml of acetone were added 10.0 g of D-mannose and 89.7 mg of antimony pentachloride, and the mixture was refluxed with stirring in a water bath of 60° C. for 8 hours. During this reaction, the refluxing solvent was dried with 20 g of Molecular Sieves 3A interposed between the reaction vessel and the condenser. After completion of the reaction, a small amount of pyridine was added to the reaction mixture, and the acetone was distilled off under reduced pressure. The residue was dissolved in benzene, and the solution was washed with aqueous sodium bicarbonate and water, and dried over anhydrous magnesium sulfate. The benzene was distilled off under reduced pressure to give 11.61 g (80.4%) of 2,3:5,6-di-O-isopropylidene-α-D-mannofuranose as a residue. The compound, when recrystallized from petroleum ether, showed m.p. 122°-123° C.

1. temperaturethe mixture was refluxed
2. customDuring this reaction
3. dry with materialthe refluxing solvent was dried with 20 g of Molecular Sieves 3A
4. customAfter completion of the reaction
5. distillationthe acetone was distilled off under reduced pressure
6. dissolutionThe residue was dissolved in benzene
7. washthe solution was washed with aqueous sodium bicarbonate and water
8. dry with materialdried over anhydrous magnesium sulfate
9. distillationThe benzene was distilled off under reduced pressure