Potassium Carbonate → Tert-butyl 3-(4,6-bistrifluoromethylpyridin-2-yl)propylcarbamate

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of tert-butyl allylcarbamate (1.95 g, 12.4 mmol) in THF (12 mL), 0.5 mol/L 9-borabicyclo[3.3.1]nonane (29.8 mL, 14.9 mmol) was added under argon atmosphere at room temperature. After stirred at room temperature for 4 h, a solution of 2-bromo-4,6-bistrifluoromethylpyridine (3.65 g, 12.4 mmol) in DMF (12 mL), Pd(OAc)2 (278 mg, 1.24 mmol), DPPF (859 mg, 1.55 mmol) and K2CO3 (2.92 g, 21.1 mmol) were added to the reaction mixture and stirred at room temperature for 7 h. To the reaction mixture, water was added and the crude product was extracted with EtOAc, washed with brine, dried over NaSO4 and the solvent was removed in vacuo. The crude product was purified by column chromatography (Hexane:EtOAc 10:1→2:1) to yield tert-butyl 3-(4,6-bistrifluoromethylpyridin-2-yl)propylcarbamate (3.41 g, 74%) as a colorless solid. 1H NMR (CDCl3, 400 MHz) δ 1.44 (9H, s), 1.96-2.03 (2H, m), 2.98-3.02 (2H, m), 3.20-3.25 (2H, m), 4.71 (1H, brs), 7.59 (1H, s), 7.72 (1H, s). CIMS (+) 373 [M+H]+.

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