Pyridine, reactions with—continued thionyl chloride

The stream of dry air is continued for about six hours or until most of the hydrogen chloride has been expelled and then another 55 grams of thionyl chloride is added. The reaction mixture is allowed to stand twenty-four hours, a few drops of pyridine are added and the mixture heated 4 hours on the steam bath. The cooled reaction mixture is poured into water, the crude product is washed with dilute sodium bicarbonate solution and finally taken up in benzene. The benzene is distilled at ordinary pressure and the residue distilled in vacuo to yield 60-70% of Tphenoxy-2-chloropropane, BP 93°-94°C/5 mm. 

Preparation of sulfonamide 4 A mixture of thiol compound (1 2 mmol), 30% hydrogen peroxide (6 mmol, 0.6 mL) and thionyl chloride (2 mmol, 0.14 mL) was stirred in acetonitrile at room temperature for an appropriate time. After completion of the reaction as indicated by TLC, a solution of amine (3 2 mmol) in pyridine (1 mL) was added to the reaction mixture. The resulting mixture was then continued to stir at room temperature until completion of the reaction. On completion of the reaction, the resulting mixture was acidified with 2 N HCl solution, and extracted with EtOAc. The organic layer was washed with water and brine, and dried over magnesium sulfate. The filtrate was evaporated to obtain pure sulfonamide derivative 4 crystalline solid. Recrystallization from a mixture of ethanol and water afforded analytically pure product. AU the products were characterized by analytical and spectral studies. 

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