To a solution of 2-(3-amino-5-chloro-pyridin-2-yloxy)-1-[4-(4-fluoro-benzyl)-(2R,5S)-2,5-dimethyl-piperazin-1-yl]-ethanone (0.072 g, 0.18 mmol) in ethanol (1 mL) was added 4-bromo-butyric acid ethyl ester (0.030 mL, 0.21 mmol), sodium bicarbonate (0.031 g, 0.37 mmol) and potassium iodide (˜0.030 g). The resulting solution was stirred at 70° C. for 18 hours. Additional bromo-butyric acid ethyl ester (0.030 mL, 0.21 mmol) was added and the reaction was stirred at 70° C. for 18 hours. The reaction was cooled, concentrated in vacuo and purified via flash chromatography on silica gel to give the title compound (0.034 g).
