Reaktion #74465

Reaktionsgleichung

boron trifluoride diethyl etherate

(3R,4S,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxymethyl)-2-(4-chloro-3-((triisopropylsilyloxy)methyl)phenyl)tetra-hydro-2H-pyran-2-ol

(3R,4S,5R,6R)-3,4,5-Tris(benzyloxy)-6-(benzyloxymethyl)-2-(4-chloro-3-((triisopropylsilyloxy)methyl)phenyl)-tetrahydro-2H-pyran-2-ol

triethylsilane

→

title compound

(2-Chloro-5-((3S,4R,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxymethyl)-tetrahydro-2H-pyran-2-yl)benzyloxy)triisopropylsilane

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas maintained between −40 and −50° C
2. 2
   Sonstigeto quenching with saturated potassium carbonate solution
3. 3
   SonstigeAfter removal of organic volatiles under reduced pressure
4. 4
   Sonstigethe residue was partitioned between ethyl acetate and water
5. 5
   Extraktionextraction of the aqueous layer with ethyl acetate
6. 6
   Waschenthe combined organic layers were washed with water
7. 7
   Trocknento drying over magnesium sulfate
8. 8
   FiltrationFiltration and concentration under reduced pressure

Vorschrift

To a stirred −50° C. solution of (3R,4S,5R,6R)-3,4,5-tris(benzyloxy)-6-(benzyloxymethyl)-2-(4-chloro-3-((triisopropylsilyloxy)methyl)phenyl)tetra-hydro-2H-pyran-2-ol (198 mmol) from Step 4 in dichloromethane (500 mL) was added triethylsilane (63 mL, 396 mmol) followed by boron trifluoride diethyl etherate (50 mL, 396 mmol) at a rate such that the reaction temperature was maintained between −40 and −50° C. The solution was allowed to warm to −10° C. over 2 h prior to quenching with saturated potassium carbonate solution. After removal of organic volatiles under reduced pressure, the residue was partitioned between ethyl acetate and water. Following extraction of the aqueous layer with ethyl acetate, the combined organic layers were washed with water prior to drying over magnesium sulfate. Filtration and concentration under reduced pressure yielded the title compound as a yellow oil which was used without further purification.

Quelle