反应详情

To a solution of tert-butyl (4R)-4-((1R,2S)-1-{[tert-butyl(dimethyl)silyl]oxy}-2-cyclopropyl-3-hydroxypropyl)-2,2-dimethyl-1,3-oxazolidine-3-carboxylate (1.3 g, 3.0 mmol) and triphenylphosphine (1.6 g, 6.1 mmol) in anhydrous THF (20 mL), DIAD (1.2 mL, 5.9 mmol) was added drop-wise under an atmosphere of nitrogen. Upon completion of addition, a precipitate was formed. The reaction mixture was stirred for 30 min. then diphenylphosphonic azide (1.3 mL, 6.2 mmol) in anhydrous THF (1.0 mL) was added. After stirring at ambient temperature for 3 h, the volatile organic solvents were removed under reduced pressure and the crude product was purified by flash column chromatography (120 g of silica gel, eluting with 0-15% EtOAc-hexanes) to afford the sub-title compound as a light yellow oil (1.18 g, 86%). LC/MS (ESI) m/z calc. for C17H35N4O2Si: 355.30 [M-Boc+H]+. found: 355.1.

1. additionUpon completion of addition
2. customa precipitate was formed
3. stirringAfter stirring at ambient temperature for 3 h
4. customthe volatile organic solvents were removed under reduced pressure
5. customthe crude product was purified by flash column chromatography (120 g of silica gel, eluting with 0-15% EtOAc-hexanes)