反应详情

N-(3-methyl-5-isoxazolyl)-5-bromothiophene-2-sulfonamide was prepared in the same manner as described in Example 14 from 5-bromothiophene-2-sulfonyl chloride and 5-amino-3-methyl isoxazole. Purification was achieved by extraction of the crude sulfonamide into aqueous 2N NaOH, washing of the aqueous layer with ethyl acetate and acidification, using concentrated HCl, to pH ~2. Re-extraction into ethyl acetate was followed by washing of the organic material with water, brine and drying over magnesium sulfate. After evaporation of solvents, a brownish solid remained which was sufficiently pure to use in the next step.

1. customPurification
2. extractionwas achieved by extraction of the crude sulfonamide into aqueous 2N NaOH
3. washwashing of the aqueous layer with ethyl acetate and acidification
4. washby washing of the organic material with water, brine
5. dry with materialdrying over magnesium sulfate
6. customAfter evaporation of solvents