A PROCESS FOR PREPARING PURIFIED ALKALI METAL SALTS OF 4-SULFOPHENYL-[(1-OXYALKANOYL)AMINO]ALKANOATE WITHOUT ISOLATION OF INTERMEDIATES

摘要

This invention relates to a five step process for preparing a purified alkali metal salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate in one reaction vessel without isolation of intermediates. The first step involves reacting an alkali metal salt of 4-hydroxybenzenesulfonic acid with a C2 to C4 carboxylic anhydride in a solvent to form an alkali metal salt of 4-acyloxybenzenesulfonic acid and a C2 to C4 carboxylic acid. The second step involves adding an [(1-oxyalkanoyl)amino]alkanoic acid and a transesterification catalyst to the reaction product of Step (A) and heating at a temperature and pressure sufficient to maintain reflux of the solvent and to remove the C2 to C4 carboxylic acid from the reaction vessel to form a reaction mixture containing an alkali metal salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate. The third step involves removing solvent from the reaction mixture formed in Step (B). The fourth step involves mixing the alkali metal salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate product of Step (C) with acetic acid. The fifth step involves separating the product from the acetic acid. The purified alkali metal salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate product is useful as a bleach activator in detergents.