反应详情

16.0 g (127 mmol) of levoglucosenone was dissolved in 700 ml of water, followed by adding 8.00 g (211 mmol) of sodium borohydride to! the solution. The resultant system was kept stirred at room temperature for 5 minutes. Then, 400 ml of acetone was added to the mixture, and solvent was removed by distillation under reduced pressure, followed by adding chloroform to the residue so as to remove insoluble components by means of filtration. The filtrate was distilled under reduced pressure so as to remove the solvent. Further, the residue was recrystallized from a mixed solvent consisting of 4 parts of hexane and 1 part of diethyl ether so as to obtain 5.55 g of 1,6-anhydro-3,4-dideoxy-β-D-threo-hex-3-enopyranose (compound 2). The yield of the compound 2 was 34.1%. Further, the mother liquor after the recrystallization was refined with a silica gel column chromatograph by using, as an eluent, a mixed solvent consisting of 1 part of hexane and 1 to 2 parts of ether, and recrystallization was achieved again using a mixed solvent consisting of 1 part of hexane and 3 parts of ethyl acetate so as to obtain 2.14 g of the compound (2). The total yield of the compound (2) was 7.69 g, i.e., 60.1%. The 1H-NMR spectrum of the compound (2) thus obtained was found to be as follows, which was equal to that of the compound (2) obtained in step a) of Example 1:

1. customwas removed by distillation under reduced pressure
2. additionby adding chloroform to the residue so as
3. customto remove insoluble components
4. filtrationby means of filtration
5. distillationThe filtrate was distilled under reduced pressure so as
6. customto remove the solvent
7. customFurther, the residue was recrystallized from a mixed solvent