General procedure for the synthesis of pyridine-3-sulfonamide from pyridine-3-sulfonyl chloride:
Intermediate 78: Pyridine-3-sulfonamide; To a solution of pyridine-3-sulfonyl chloride (1 g, 5.6 mmol, 1 eq., commercially available from Davos) in tetrahydrofuran (THF, 5 mL) was added a solution of ammonia in dioxane (23.9 mL, 2 M, 47.9 mmol, 8.5 eq.). The resulting suspension was stirred at room temperature for 1 hour. After completion of the reaction, the solvent was removed by rotary evaporation and the residue was dissolved in dichloromethane (DCM). The organic phase was washed sequentially with saturated aqueous ammonium chloride (NH4Cl) and brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to remove the DCM. the product was dried under vacuum at 40 °C to afford 637 mg (71% yield) of the title compound as a pale yellow powder.1H NMR (DMSO-d6) δ 9.20-8.90 (m, 1H), 8.85-8.75 (m. 1H), 8.40-8.05 (m, 1H), 7.80-7.40 (m, 3H).