To a solution of 2-anilino-7-chloro-1-phenyl-5-(trifluoromethyl)-1,8-naphthyridin-4(1H)-one (100.0 mg, 0.241 mmol) in dioxane (2.5 mL) was added piperdine (40.9 mg, 0.481 mmol). The mixture was left to stir at 80° C. overnight. The mixture was cooled to room temperature, poured into 1N HCl (1 mL) and extracted with CH2Cl2. The organic extracts were combined, washed with saturated aqueous NaHCO3, dried over Na2SO4, and concentrated in vacuo. The residue was purified by Biotage silica gel chromatography (1:1 EtOAc:Hex) to provide 2-anilino-1-phenyl-7-(1-piperidinyl)-5-(trifluoromethyl)-1,8-naphthyridin-4(1H)-one (89.5 mg, 80%) as a pale yellow solid: LCMS RT: 2.76 min, MH+: 465.5.
