To a stirred solution of (2-chloro-6-(trifluoromethyl)pyridin-3-yl)methanamine (2.9 g, 13.8 mmol) and 2-(3-fluoro-4-(methylsulfonamidomethyl)phenyl)propanoic acid (3.8 g, 13.8 mmol) in tetrahydrofuran (100 mL) were added 1-hydroxybenzotriazol (1.89 mL, 13.8 mmol), O-(1H-benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (4.4 g, 13.8 mmol) and N-ethyldiisopropylamine (7 mL, 41.4 mmol) to gave an suspension. After addition of N,N-dimethylformamide (1 mL) the reaction mixture was stirred for 36 h at room temperature. The reaction mixture was concentrated under reduced pressure and the solid obtained was purified by column chromatography (silica gel: 100-200 mesh, eluent: cyclohexane/ethyl acetate 1:2) to afford N-((2-chloro-6-(trifluoromethyl)pyridin-3-yl)methyl)-2-(3-fluoro-4-(methylsulfonamidomethyl)phenyl)propanamide (3.96 g, 61%).
