反应详情

1-((Fluoromethyl)sulfinyl)-4-methylbenzene (738 mg, 4.29 mmol) of example 5 was dissolved in dry diethyl ether (15 mL) under an argon atmosphere. Cumene (0.66 mL, 1.1 eq) was added to the previous solution and then the mixture was cooled to a temperature below −50° C. After stabilizing the temperature, trifluoromethanesulfonic anhydride (0.72 mL, 1 eq) was added slowly maintaining the same temperature. The mixture was stirred, at the same temperature, until the reaction was complete. HBF4 in diethyl ether solution (54%, 1.18 mL, 2 eq) was added. The resulting suspension was stirred for 30 minutes. The precipitate tetrafluoroborate salt was isolated by filtration and washed with diethyl ether at 0° C. The desired product was obtained as a slightly yellow oily solid (2.22 g) after heating at room temperature.

1. temperaturethe mixture was cooled to a temperature below −50° C
2. additionwas added slowly
3. temperaturemaintaining the same temperature
4. stirringThe resulting suspension was stirred for 30 minutes