3-Amino-1H-pyrazole-4-carboxamide (0.80 g, 6.3 mmol) and tert-butyl 4-(cyanomethylene)piperidine-1-carboxylate (2.1 g, 9.5 mmol) were combined with acetonitrile (31 mL) in a pressure vessel. DBU (1.05 mL, 6.98 mmol) was then added at ambient temperature. The reaction vessel was sealed and the mixture was heated to 80° C. for 16 hours. The reaction mixture was then allowed to cool to ambient temperature before water (150 mL) was added. The aqueous mixture was extracted with EtOAc (2×). The organic layers were then combined and washed with brine, dried over anhydrous MgSO4, filtered, and concentrated in vacuo. The crude residue was adsorbed on silica gel in vacuo and purified by MPLC on silica gel (using a gradient elution of 75-100% EtOAc/hexanes) to afford the title compound, Intermediate #35-1.
