A mixture of 2-(5-bromo-pyridin-3-yl)-3,3-dimethyl-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester (8.5 g, 21.94 mmol), morpholine (19.1 mL, 219.3 mmol), copper(I) iodide (1.7 g, 8.8 mmol), N,N-dimethylglycine hydrochloride (2.5 g, 17.5 mmol) and potassium carbonate (9.1 g, 65.8 mmol) in dimethyl sulfoxide (35 mL) was stirred at 120° C. for 16 h. Then the reaction mixture cooled to room temperature. The reaction mixture was extracted with ethyl acetate (2×150 mL), washed with water (2×50 mL) and saturated aqueous ammonium chloride solution (2×50 mL), dried over anhydrous sodium sulfate and then concentrated in vacuo to afford 3,3-dimethyl-2-(5-morpholin-4-yl-pyridin-3-yl)-1,2,3,4-tetrahydro-quinoline-6-carboxylic acid ethyl ester (3.5 g, 40.4%) as a white solid which was used for next step without further purification: LC/MS m/e calcd for C23H29N3O3 (M+H)+: 396.53, observed: 396.1.
