A 25 mL scintillation vial was charged with 4-tert-butyl-N-(4-chloro-2-pyrazol-1-yl-phenyl)-benzenesulfonamide (synthesized according to general procedure D, 78 mg, 0.2 mmol), N-chlorosuccinimide (67 mg, 0.5 mmol), benzoyl peroxide (2.4 mg, 0.01 mmol), and carbon tetrachloride (4 mL). The vial was sealed and stirred for 18 hours at 80° C. The resultant solution was partitioned between ethyl acetate and water and the combined organics were washed with 1 N HCl, saturated sodium bicarbonate, and brine; dried over magnesium sulfate; filtered; and concentrated in vacuo. The crude product was subsequently purified by flash column chromatography (10-100% ethyl acetate in hexanes) followed by preparative HPLC (10-90% gradient of MeCN:water) to afford the title compound as a white solid: MS (ES) M+H expected 424.1, found 424.1.
