反应详情

DIAD (33.5 g) was added dropwise to the solution of triphenylphosphine (43.5 g), 4-bromo-2-trifluoromethylphenol (40 g) and tert-butyl 4-(2-hydroxyethyl)-piperidine-1-carboxylate (31.7 g) in DCM (200 ml) at 0° C. during 15 minutes. The mixture was then stirred at room temperature for 20 hours. After removal of DCM under reduced pressure, to the residue was added ether (100 ml) and heptane (300 ml), solid was then filtered off. Filtrate was then washed with 1M sodium hydroxide (100 ml×3). Organic layer dried over sodium sulphate, solvent removed under vacuum, residue was then columned on silica gel using heptane:EtOAc (5:1) as eluant to give tert-butyl 4-(2-(4-bromo-2-(trifluoromethyl)phenoxy)ethyl)piperidine-1-carboxylate as a colorless oil as product (61.3 g).

1. customAfter removal of DCM under reduced pressure
2. additionto the residue was added ether (100 ml) and heptane (300 ml), solid
3. filtrationwas then filtered off
4. washFiltrate was then washed with 1M sodium hydroxide (100 ml×3)
5. dry with materialOrganic layer dried over sodium sulphate, solvent
6. customremoved under vacuum, residue