Molecular Formula | C12H15BF3NO2 |
Molar Mass | 273.06 |
Density | 1.18±0.1 g/cm3(Predicted) |
Boling Point | 313.6±42.0 °C(Predicted) |
pKa | 2.80±0.22(Predicted) |
Storage Condition | under inert gas (nitrogen or Argon) at 2-8°C |
application | 5-trifluoromethylpyridine-3-borate pinacol ester can be used as organic synthesis intermediates and pharmaceutical intermediates, mainly used in laboratory research and development and chemical production. |
preparation | add 3-bromo -5-(trifluoromethyl) pyridine to a 500 mL three-neck bottle, 150 mL dry tetrahydrofuran, stir evenly under argon protection, slowly add 40mL n-butyl lithium drop below 5 ℃, after dropping, react at room temperature for 1 hour, then cool down to -80 ℃, add 15 mL trimethyl borate dropwise, and stir at -80 ℃ for 0.5 hours. Slowly raise the temperature to room temperature, add 150 mL 15% ammonium chloride solution dropwise to neutralize the acid in the reaction solution, and then stir for 1 hour at room temperature. The organic layer is separated, the water layer is extracted with ethyl acetate, the organic phase is combined, and the anhydrous magnesium sulfate is dried. Suction filtration, vacuum evaporation of the filtrate to dry, 1-methyl -1,2,3, 6-tetrahydropyridine-4-boric acid crude, recrystallized with 5 times the volume of water. 1-methyl -1,2,3,6-tetrahydropyridine -4-boric acid was added to 250 mL of three-necked bottle, 100 mL of dried tetrahydrofuran, 1.8g( 0.015 3 mol) pinacol, stirred and dissolved, molecular sieve was added, and stirred and reacted at room temperature for 2 hours. Filter, evaporate the filtrate to dry, dissolve with 100 mL n-hexane, wash the organic phase with water, and dry with anhydrous magnesium sulfate. Suction filtration, the filtrate is evaporated to obtain 5-trifluoromethylpyridine-3-borate pinacol ester. |