In a 50 mL round-bottomed flask was added tert-butyl 4-(4-(azetidine-3-carboxamido)phenyl)piperidine-1-carboxylate (918 mg, 2.55 mmol) and diisopropylethylamine (0.558 ml, 3.19 mmol) in ethanol (10.6 ml). 3,6-dichloropyridazine (317 mg, 2.128 mmol) was added as a solid in a single portion. The reaction was stirred overnight at 45° C.; and the reaction was cooled and concentrated. Dichloromethane and water were added and the layers were separated. The aqueous layer was extracted three times with dichloromethane and the combined organics were dried with magnesium sulfate, filtered and concentrated by rotary evaporation. The residue was purified by regular phase flash column chromatography to give the title compound.
