Potassium Carbonate → 6-chloro-4-methyl-3-(trifluoromethoxy)-1-trityl-1H-pyrazolo[4,3-c]pyridine

A mixture of 6-chloro-4-methyl-1-trityl-1H-pyrazolo[4,3-c]pyridin-3(2H)-one (Intermediate 4B, 207.1 mg, 0.486 mmol), potassium carbonate (217.6 mg, 1.574 mmol) and 1-trifluoromethyl-1,2-benziodoxol-3-(1H-one (227.3 mg, 0.719 mmol) in DMF (2 ml) was stirred at RT for 16.5 hr, then heated to 60° C. for 5 hr. Added water and filtered to collect precipitate, which was purified via flash chromatography (0-100% EtOAc/Hex) to provide 6-chloro-4-methyl-3-(trifluoromethoxy)-1-trityl-1H-pyrazolo[4,3-c]pyridine. MS: [M+H]+ m/z 494.