反应详情

温度

70 °C

A mixture of 5-(1-bromoethyl)-2-fluoropyridine (17.65 g, 87 mmol) and tert-butyl piperazine-1-carboxylate (16.92 g, 91 mmol) in acetonitrile (300 mL). was treated with potassium carbonate (14.35 g, 104 mmol) and potassium iodide (2.87 g, 17.30 mmol). The mixture was placed into a pre-heated (70° C.) bath and allowed to stir under inert atmosphere overnight. The reaction mixture was diluted with chloroform (200 mL) and water (100 mL). The organic layer was extracted with chloroform (3×50 mL). The combined organic extracts were dried over sodium sulfate, filtered and concentrated in vacuo. The crude material was adsorbed onto a plug of silica gel and purified by chromatography through a silica-gel column (330 g) eluting with 50% ethyl acetate/hexanes to give tert-butyl 4-(1-(6-fluoropyridin-3-yl)ethyl)piperazine-1-carboxylate (17.27 g, 55.8 mmol, 64.5% yield) as a yellow oil. m/z (ESI, +ve ion) 310.1 (M+H)+.

1. extractionThe organic layer was extracted with chloroform (3×50 mL)
2. dry with materialThe combined organic extracts were dried over sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. custompurified by chromatography through a silica-gel column (330 g)
6. washeluting with 50% ethyl acetate/hexanes