Potassium Carbonate → 3-Ethynyl-7-trifluoromethyl-5-(4-trifluoromethyl-phenyl)-pyrazolo[1,5-a]pyrimidine

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Reaction Conditions

Reaction Steps

To a solution of 7-trifluoromethyl-5-(4-trifluoromethyl-phenyl)-3-trimethylsilanylethynyl-pyrazolo[1,5-a]-pyrimidine (Example C.1 step 3a) (13.65 g, ca. 26 mmol) in THF (40 mL) and MeOH (100 mL) at 0° C. was added K2CO3 (362 mg, 10 mol %), and the mixture was stirred at 0° C. for 6 h. Diluted with TBME and ice water, separated phases, washed organic layer with brine, dried over Na2SO4. Removal of the solvent in vacuum left a dark brown solid, which was purified by silica gel column chromatography with heptane/EtOAc 9:1 followed by trituration with heptane to give the 3-ethynyl-7-trifluoromethyl-5-(4-trifluoromethyl-phenyl)-pyrazolo[-1,5-a]pyrimidine (7.90 g, 89%) as a yellow solid. MS (ISP) 356.0 [(M+H)+]; mp 138° C.

Provenance & Evidence