反应详情

A mixture 4-chloro-N-[5-chloro-2-(2-nitro-benzoyl)-pyridin-3-yl]-N-methoxymethyl-3-trifluoromethyl-benzenesulfonamide (580 g, 1.02 mmol) in 4 M HCl in dioxane (15 mL), and water (5 mL) was heated at 100° C. for 8 h and then at room temperature for 10 h. The reaction mixture was concentrated to dryness under reduced pressure and it was treated with aqueous NaHCO3 to adjust pH to 5-6 and extracted with EtOAc. The combined extracts were dried (Na2SO4), filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to provide the desired product 4-Chloro-N-[5-chloro-2-(2-nitro-benzoyl)-pyridin-3-yl]-3-trifluoromethyl-benzenesulfonamide. 1H NMR (400 MHz, CDCl3) δ 11.06 (s, 1 H), 8.23 (d, J=2.4 Hz, 1 H), 8.18 (d, J=2.4 Hz, 1 H), 8.14 (dd, J=8.0, 1.4 Hz, 1 H), 8.07 (d, J=2.4 Hz, 1 H), 8.00 (dd, J=8.4, 2.0 Hz, 1 H), 7.80-7.77 (m, 1 H), 7.70-7.66 (m, 2 H), 7.45 (dd, J=8.0, 1.6 Hz, 1 H); Mass spectrum m/z: 520.2 (M+H).

1. concentrationThe reaction mixture was concentrated to dryness under reduced pressure and it
2. additionwas treated with aqueous NaHCO3
3. extractionextracted with EtOAc
4. dry with materialThe combined extracts were dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by flash column chromatography on silica gel