1-(3-Dimethylaminopropyl)-3-ethylcarboiimide hydrochloride (138 mg, 0.72 mmol) was added to a solution of O-(1-(3-(trifluoromethyl)phenylsulfonyl)piperidin-4-yl)hydroxylamine (195 mg, 0.60 mmol), 1-hydroxybenzotriazole (97.0 mg, 0.72 mmol), 4-chlorobenzoic acid (94.0 mg, 0.60 mmol) and N,N-diisopropylethylamine (233 mg, 1.80 mmol) in N,N-dimethylformamide (6 ml). The reaction mixture was stirred at room temperature for 17 hours and quenched with H2O (8 ml) and aqueous 1 N HCl solution (pH=3). The aqueous phase was extracted with CH2Cl2 (20 ml×3) and the combined organic phase was washed with aqueous NaHCO3 solution and brine, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by column chromatography (ethyl acetate/hexane: 67/33) to give 4-chloro-N-(1-(3-(trifluoromethyl)phenylsulfonyl)piperidin-4-yloxy)benzamide (172 mg, 62%) as a white solid: LCMS: 463 [M+1]+. 1H NMR (DMSO-d6) δ: 1.70 (m, 2H), 1.90 (m, 2H), 3.01 (m, 2H), 3.13 (m, 2H), 3.98 (d, 1H), 7.51 (d, 2H), 7.68 (m, 2H), 7.95 (m, 2H), 8.11 (m, 2H), 11.6 (s, 1H).
