Cyclohexanone → 2,3:5,6-DI-O-Cyclohexylidene-alpha-D-mannofuranose

Participants

Reaction Conditions

Reaction Steps

To a mixed solution consisting of 100 ml of cyclohexanone and 100 ml of dichloromethane 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 68° 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. The reaction mixture was diluted with benzene, washed with aqueous sodium bicarbonate and water, and dried over anhydrous magnesium sulfate. The solvents including cyclohexanone were distilled off under reduced pressure to give 16.49 g (87.3%) of 2,3:5,6-di-O-cyclohexylidene-α-D-mannofuranose as a residue. The compound, when recrystallized from cyclohexane, showed m.p. 122°-124° C.

Provenance & Evidence