反应详情

温度

70 °C

To a 100 mL round-bottomed flask was added 5-(1-bromoethyl)-2-fluoropyridine (3.9 g, 19.11 mmol), acetonitrile (75 mL, 1435 mmol), (R)-4-N-boc-2-methyl-piperazine (4.02 g, 20.07 mmol), (Aldrich), potassium carbonate (1.384 mL, 22.94 mmol), (Aldrich), potassium iodide (0.205 mL, 3.82 mmol), (Fluka). The reaction mixture was stirred at 70° C. overnight. The reaction mixture was diluted with water (50 mL) and DCM (50 mL) and extracted with DCM (3×50 mL) dried over sodium sulfate, filtered and concentrated under a vacuum to give (3R)-tert-butyl 4-(1-(6-fluoropyridin-3-yl)ethyl)-3-methylpiperazine-1-carboxylate (3.05 g, 9.43 mmol, 49.3% yield). The crude product was adsorbed onto a plug of silica gel and chromatographed through a silica gel column (80 g), eluting with a gradient of 0% to 50% EtOAc in hexane, to provide (3R)-tert-butyl 4-(1-(6-fluoropyridin-3-yl)ethyl)-3-methylpiperazine-1-carboxylate (3.05 g, 9.43 mmol, 49.3% yield).

1. extractionextracted with DCM (3×50 mL)
2. dry with materialdried over sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated under a vacuum