Reaktion #64318

Reaktionsgleichung

acetic acid

ethyl acetate

ethanol

sodium borohydride

diphenyl diselenide

ethanol

→

1,6-anhydro-3-deoxy-β-D-threo-hexopyranos-2-ulose

Ausbeute 80.6%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat room temperature
2. 2
   Temperaturcooling
3. 3
   workup.ADDITIONwas added dropwise
4. 4
   workup.STIRRINGAfter the reaction mixture was stirred for 2 hours while ice-
5. 5
   Temperaturcooling
6. 6
   workup.ADDITIONdiluted
7. 7
   SonstigeAfter a solvent was removed from the reaction solution under reduced pressure
8. 8
   Sonstigethe residue was purified by means of silica gel column chromatography (hexane: ethyl acetate=1:2)

Vorschrift

0.47 g (1.50 mmol) of diphenyl diselenide dissolved in 7.5 ml of dry ethanol and 0.11 g (3.00 mmol) of sodium borohydride was gradually added thereto at room temperature. After the reaction mixture was stirred for 5 minutes, 11.6 ml of acetic acid was added to the reaction mixture while ice-cooling. Then, 0.16 g (1.00 mmol of 1,6:3,4-dianhydro-β-D-lyxo-hexopyranos-2-ulose monohydrate represented by the above formula [5'] dissolved in 8 ml of a dry ethanol was added dropwise thereto. After the reaction mixture was stirred for 2 hours while ice-cooling, a temperature thereof was raised to room temperature and diluted by adding 78 ml of ethyl acetate. After a solvent was removed from the reaction solution under reduced pressure, the residue was purified by means of silica gel column chromatography (hexane: ethyl acetate=1:2), thereby obtaining 0.12 g (yield: 80.6%) of 1,6-anhydro-3-deoxy-β-D-threo-hexopyranos-2-ulose represented by the following formula [6]. This was recrystallized from a hexane-diethyl ether mixed solvent. ##STR15##

Quelle