Dissolve N-[2-[2-bromo-1-(3-methoxyphenyl)ethoxy]ethyl]-4-nitro-benzenesulfonamide (14.22 g, 30.96 moles) in ACN (200 mL); add potassium carbonate (6.42 g, 46.44 mmol); and heat the mixture to reflux. Stir the mixture for 3 h while refluxing. Cool the resulting mixture to ambient temperature and dilute it with EtOAc. Filter through Celite®; concentrate the filtrate under reduced pressure to provide a residue. Purify the residue via flash column chromatography eluting with a 50-80% gradient of EtOAc in hexanes. Combine the product fractions and remove the solvents under reduced pressure to provide the title compound as an orange solid (11.2 g, 95.6%). MS (m/z): 379 (M+1).
