Sulfuric Acid → HCID 14700386, compound

Participants

Reaction Steps

To a stirred solution of 4-[1-(methoxyethoxymethoxy)propyl]-5-methylsulfonylthiophene-2-sulfonamide (8.0 g, 0.02 mol) in methanol (20 ml) was added a cold solution of concentrated sulfuric acid (20 ml) in water (20 ml). The mixture was stirred at room temperature for 1 hour and the solution was basified with a slight excess of 40% NaOH and the suspension was filtered to remove precipitated salts. The filtrate was washed with ether and acidified with HCl. The acidified mixture was extracted with ethyl acetate (4×25 ml). The combined extracts were washed with saturated NaCl solution and dried over anhydrous Na2SO4. The solution was filtered and concentrated in vacuo at room temperature to give a viscous yellow oil which was a mixture of five components. Chromatography on 300 g of silica gel eluting with 5% methanol/CHCl3 gave 3.0 g of a pure colorless oil. Trituration of the oil in n-butyl chloride gave a white solid (2.8 g) (45%). The product was recrystallized from 1,2-dichloroethane; m.p. 125.5-126.5° C.

Provenance & Evidence