A solution of 2-(2-bromo-phenyl)-6-chloro-4,4-dimethyl-1,2,3,4-tetrahydro-quinoline (200 mg, 0.57 mmol), copper(I) iodide (33 mg, 0.17 mmol), 1-amino-cyclopropanecarboxylic acid (235 mg, 2.29 mmol) and potassium carbonate (240 mg, 1.7 mmol) in dimethyl sulfoxide (2.0 mL) was stirred at 120° C. for 16 h. Then the reaction mixture was cooled to room temperature and extracted with ethyl acetate (150 mL×2), washed with water (50 mL×2) and saturated aqueous ammonium chloride solution (50 mL×2), dried over anhydrous sodium sulfate and then concentrated in vacuo. Purification by Waters automated flash system (column: Xterra 30 mm×100 mm, sample manager 2767, pump 2525, detector: ZQ mass and UV 2487, solvent system: acetonitrile and 0.1% ammonium hydroxide in water) afforded 2-[2-(6-chloro-4,4-dimethyl-1,2,3,4-tetrahydro-quinolin-2-yl)-phenylamino]-2-methyl-propionic acid (127 mg, 60.0%) as a white solid: LC/MS m/e obsd. (ESI+) [(M+H)+] 371.1.
