A mixture of 4-bromo-2-{[(2,4-dimethoxy-phenoxy)-ethoxycarbonylmethyl-amino]-methyl}-benzoic acid ethyl ester (3.271 g), 4-chloro-3-fluoro-phenol (1.94 g), CuCl (328 mg), 2,2,6,6-tetramethyl-heptane-3,5-dione (TMHD, 0.26 mL), cesium carbonate (4.31 g) in NMP (6 mL) was heated at 130° C. for 24 h. The cooled, diluted with EtOAc, solids were filtered off, filtrate was washed with water, diluted NaCl solution, dried over sodium sulfate, filtered off, concentrated, the residue was column purified to give the desired product (2.529 g). LC MS ESI+: 561 (M+1)+.
