Cesium carbonate → HCID 118390791, compound

Participants

Reaction Conditions

Reaction Steps

A 20 mL microwave vial was charged with cesium carbonate (907 mg, 2.78 mmol), tert-butyl(6-chloro-1-trityl-1H-pyrazolo[4,3-c]pyridin-3-yl)(ethyl)carbamate (500 mg, 0.928 mmol), benzyl carbamate (421 mg, 2.78 mmol), 2-(dicyclohexylphosphino)3,6-dimethoxy-2′,4′,6′-triisopropyl-1,1′-biphenyl (34.9 mg, 0.065 mmol) and BrettPhos-G3-Pd (58.9 mg, 0.065 mmol). Dioxane (10 ml) was added, the vial was flushed with argon, capped and the contents heated to 100° C. with stirring for 16 h. The reaction mixture was diluted with DCM/i-PrOH (4:1, 50 mL) and washed with brine (2×50 mL), dried (MgSO4), filtered and the solvent was evaporated under reduced pressure. The resulting residue was purified by flash column chromatography on silica gel (ISCO; 24 g prepacked) eluting with ethyl acetate/hexanes to afford tert-butyl(6-(((benzyloxy)carbonyl)amino)-1-trityl-1H-pyrazolo[4,3-c]pyridin-3-yl)(ethyl)carbamate (225 mg, 0.344 mmol, 37.1% yield) as a white solid. MS ESI calc'd. For C40H40N5O4 [M+H]+ 654. found 654.

Provenance & Evidence