(Diethylamino)sulfur trifluoride → 1-Benzyl-3-(2,3-difluorophenyl)-3-fluoropyrrolidine

Beteiligte Stoffe

Reaktionsschritte

To a solution of 1-benzyl-3-(2,3-difluorophenyl)pyrrolidin-3-ol (5.3 g, 18.3 mmol) in dichloromethane (30 mL) at 0° C. was added drop wise, a solution of diethylaminosulfur trifluoride (2.93 mL, 22.4 mmol) in dichloromethane. The cooling was removed and the mixture was stirred at ambient temperature for 2 h after which an additional amount of diethylaminosulfur trifluoride (0.1 mL, 0.76 mmol) was added. The mixture was stirred for 1 h at ambient temperature after which aqueous sodium hydrogen carbonate (10%) was added and the mixture was extracted with ethyl acetate. The organic phase was dried (Na2SO4), filtered and evaporated. Purification by flash chromatography on silica gel (isooctane/ethyl acetate, 1:0 to 1:1) gave the title compound (2 g). MS m/z (relative intensity, 70 eV) 291 (M+, 32), 200 (18), 133 (54), 91 (bp), 65 (20).

Herkunft & Nachweise