反应详情

Sodium azide (1.0 g) is added to a solution of tetraethyleneglycol dimethanesulphonate (5.25 g, 15 mmol), obtained according to A. W. Chwabacher et al. (J. Org. Chem. 1998, 65(5), 1717), in 18 mL of 95° ethanol. The reaction mixture is taken to reflux for 24 hours. Then the solvent is evaporated off, the reaction crude is added to 100 mL of salt water and extracted with ether 3×100 mL. The organic phase is dried over MgSO4, filtered and concentrated under reduced pressure. The residue obtained is purified by chromatography on a silica column using a gradient of AcOEt in hexane (1/1 to 3/1) as eluents. 2-(2-(2-(2-azidoethoxy)ethoxy)ethoxy)ethyl mono-methanesulphonate 47 (2.10 g, 47%) is obtained, which is used directly in the following stage.

1. customobtained
2. temperatureto reflux for 24 hours
3. customThen the solvent is evaporated off
4. customthe reaction crude
5. extractionextracted with ether 3×100 mL
6. dry with materialThe organic phase is dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe residue obtained
10. customis purified by chromatography on a silica column