Into a 250-mL round bottom flask, was placed a solution of 5-chloro-N-(5-(3,4-dimethylphenyl)pyrazin-2-yl)-2-nitrobenzamide (3.66 g, 9.56 mmol, 1.00 equiv) in N,N-dimethylformamide (80 mL), piperidine (3.8 g, 44.71 mmol, 4.70 equiv), and potassium carbonate (3.96 g, 28.70 mmol, 3.00 equiv). The resulting solution was stirred for about 8 h at 85° C. in an oil bath. The reaction was then quenched with 450 mL of water. The resulting solution was extracted with 3×300 mL of ethyl acetate and the organic layers combined, dried over anhydrous sodium sulfate, and concentrated under vacuum. This resulted in 3.86 g (crude) of N-(5-(3,4-dimethylphenyl)pyrazin-2-yl)-2-nitro-5-(piperidin-1-yl)benzamide as a yellow solid.
