反应详情

A mixture of (R)-[3-(3-fluorophenyl)-2-oxo-5-oxazolidinyl]methyl azide (PREPARATION 16. 8.200 g, 34.71 mol) in ethyl acetate (100 ml) is treated with palladium on carbon (10%, 0.820 g) under nitrogen. The atmosphere is then replaced with hydrogen (balloon) via repeated evacuation and filling. Alter stirring under hydrogen for 17 hr, TLC in methanol/chloroform (5/95) reveals the azide starling material is consumed. The atmosphere is replaced with nitrogen and then pyridine (6 ml) and acetic anhydride (4.1 ml, 43-40 mmol) are added to the reaction mixture. The reaction mixture is stirred for 1 hr at 20°-25° and then filtered through Celite, washing the pad with ethyl acetate. The flitrate is concentrated under reduced pressure and the residue taken-up in dichloromethane. The addition of ether affords a precipitate. After standing in the refrigerator overnight the solids are collected by vacuum filtration, washed with cold hexane, and dried under reducedpressure to give the title compound as a solid. The crude product is purified by chromatography over silica gel, eluting with methanol/chloroform (5/95). The appropriate fractionsare pooled and concentrated to give the title compound, mp 140.0°-140.5°; [α]25 D -6.6° (c 1.0, CHCl3).

1. customis consumed
2. stirringThe reaction mixture is stirred for 1 hr at 20°-25°
3. filtrationfiltered through Celite
4. washwashing the pad with ethyl acetate
5. concentrationThe flitrate is concentrated under reduced pressure
6. additionThe addition of ether
7. customaffords a precipitate
8. customAfter standing in the refrigerator overnight
9. filtrationare collected by vacuum filtration
10. washwashed with cold hexane
11. customdried under reducedpressure