Potassium Phosphate, Tribasic → (R)-ethyl 2-benzyl-3-oxo-6-(3-(1-phenylethyl)ureido)-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

Ethyl 2-benzyl-6-chloro-3-oxo-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate (Intermediate 12B; 71 mg, 0.214 mmol), (R)-1-(1-phenylethyl)urea (45 mg, 0.274 mmol), bippyphos (13.2 mg, 0.026 mmol), Pd2(dba)3 (5.4 mg, 5.90 μmol), and tripotassium phosphate (74 mg, 0.349 mmol) were taken up in DME (2 mL) in a 5 mL microwave vial. The vial was evacuated and back-filled with N2 (×3) and the reaction stirred at 85° C. for 2 h. Room temperature was attained and the reaction mixture filtered through Celite, eluting with MeCN. Purification of the residue by flash chromatography (12-100% EtOAc-hexanes) gave (R)-ethyl 2-benzyl-3-oxo-6-(3-(1-phenylethyl)ureido)-2,3-dihydro-1H-pyrazolo[4,3-c]pyridine-1-carboxylate. MS ESI calc'd. For C25H25N5O4 [M+1]+ 460. found 460.

Provenance & Evidence