反应详情

To an ice cold, stirred solution of the known 4-(tert-Butyl-dimethyl-silanyloxy)-but-2-yn-1-ol (3.14 g, 15.7 mmol) in THF (50 ml) was added DBU (2.6 ml, 17.4 mmol) and DPPA (3.8 ml, 17.6 mmol). The solution was warmed to room temperature and stirred under an inert atmosphere overnight. The reaction was poured into sat. NaHCO3 and the layers separated. The aqueous layer was re-extracted with EtOAc (2×) and the combined organic layers were dried (Na2SO4), and concentrated under vacuum. Triphenylphosphine (4.61 g, 17.6 mmol) was added to this crude azide dissolved in THF (50 ml), followed by addition of H20 (0.44 ml). The resultant solution was stirred overnight at room temperature, concentrated under reduced pressure and the residue was slurried in a 1:1 mixture of Et2O/pet ether. The solids were removed and the filtrate was concentrated and purified by flash chromatography on silica gel eluting CH2Cl2/MeOH (19:1) to give an amber oil. 1H NMR (CDCl3) δ 4.19 (2H, t, J=1.9 Hz), 3.33 (2H, t, J=1.9 Hz), 0.79 (9H, s), 0.00 (6H, s).

1. customthe layers separated
2. extractionThe aqueous layer was re-extracted with EtOAc (2×)
3. dry with materialthe combined organic layers were dried (Na2SO4)
4. concentrationconcentrated under vacuum
5. additionfollowed by addition of H20 (0.44 ml)
6. concentrationconcentrated under reduced pressure
7. additionthe residue was slurried in a 1:1 mixture of Et2O/pet ether
8. customThe solids were removed
9. concentrationthe filtrate was concentrated
10. custompurified by flash chromatography on silica gel
11. washeluting CH2Cl2/MeOH (19:1)
12. customto give an amber oil