Reaktion #74467

Reaktionsgleichung

(2-chloro-5-((3S,4R,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxy-methyl) tetrahydro-2H-pyran-2-yl)phenyl)methanol

compound 5

(2-chloro-5-((3S,4R,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxy-methyl) tetrahydro-2H-pyran-2-yl)phenyl)methanol

pyridine

phosphorus tribromide

→

title compound

(2S,3R,4R,5S)-3,4,5-Tris(benzyloxy)-2-(benzyloxymethyl)-6-(3-(bromomethyl)-4-chlorophenyl)-tetrahydro-2H-pyran

Lösungsmittel

ether

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturrefluxed 1 h
2. 2
   TemperaturAfter cooling to room temperature
3. 3
   Waschenwashed with water
4. 4
   ExtraktionThe organic extract
5. 5
   Trocknenwas dried over magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated in vacuo

Vorschrift

To a solution of (2-chloro-5-((3S,4R,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxy-methyl) tetrahydro-2H-pyran-2-yl)phenyl)methanol (compound 5, 130 g, 195 mmol) from Step 6 in ether (600 mL) at 0° C. was added pyridine (0.79 mL, 9.8 mmol) and phosphorus tribromide (6.4 mL, 68 mmol). The reaction was allowed to slowly warm to room temperature over 15 h and refluxed 1 h. After cooling to room temperature, the reaction mixture was diluted with ethyl acetate and washed with water then brine. The organic extract was dried over magnesium sulfate, filtered, and evaporated in vacuo to yield the title compound as a yellow oil, which was used without further purification.

Quelle