반응 #74464

반응 방정식

2,3,4,6-tetra-O-benzyl-D-glucopyranone

gluconolactone

compound 2

gluconolactone

(5-Bromo-2-chlorobenzyloxy)triisopropylsilane

compound 4

(5-Bromo-2-chlorobenzyloxy)triisopropylsilane

n-butyllithium

→

title compound

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

용매

tetrahydrofuran

tetrahydrofuran

반응 조건

후처리

1. 1
   workup.STIRRINGthe mixture was stirred for 3 h at the same temperature
2. 2
   기타The reaction mixture was quenched by addition of saturated ammonium chloride solution
3. 3
   workup.ADDITIONAfter complete addition
4. 4
   기타The organic layer was separated
5. 5
   추출the aqueous layer was extracted with ethyl acetate
6. 6
   세척The combined organic layers were washed with brine
7. 7
   건조dried over magnesium sulfate
8. 8
   여과filtered
9. 9
   농축concentrated in vacuo

실험 절차

To a solution of (5-Bromo-2-chlorobenzyloxy)triisopropylsilane (compound 4, 97 g, 257 mmol) from Step 3 in tetrahydrofuran (1 L) at −78° C. under an atmosphere of nitrogen was added dropwise n-butyllithium (2.5 M in hexanes, 103 mL, 257 mmol), and the mixture was stirred for 1.5 h at the same temperature. Then a solution of 2,3,4,6-tetra-O-benzyl-D-glucopyranone (compound 2, 106 g, 198 mmol) from Step 1 in tetrahydrofuran (500 mL) was added dropwise, and the mixture was stirred for 3 h at the same temperature. The reaction mixture was quenched by addition of saturated ammonium chloride solution. After complete addition, the solution was gradually raised to room temperature. The organic layer was separated and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, filtered and concentrated in vacuo to yield the title compound as a yellow oil which was used without further purification.

출처