A solution of 3-(2′,4′,5′-trifluoro-biphenyl-4-yloxymethyl)-benzoic acid (5.0 g, 13.96 mmol) in THF (100 mL) was treated with CDI (3.37 g, 20.78 mmol), heated at 50° C. for 30 min, cooled to room temperature, added cyclopropanesulfonamide (1.86 g, 15.35 mmol) and DBU (4.2 mL, 28.08 mmol) and heated at 60° C. for 17 h. The reaction mixture was cooled to room temperature, treated with aqueous 2N HCl (50 mL), stirred for 10 min, added water (50 mL) and extracted with ethyl acetate (3×100 mL). The organic layers were combined, washed with conc. HCl (20 mL), water (50 mL), 1/1 water/brine (50 mL), brine (50 mL), dried (MgSO4), filtered, concentrated and recrystallized from methanol to give cyclopropanesulfonic acid 3-(2′,4′,5′-trifluoro-biphenyl-4-yloxymethyl)-benzoylamide (2.58 g, 40.1%) as a white solid. LC-MS (ES) calculated for C23F18F3NO4S, 461.46; found m/z 460 [M−H]−.
