Patent ID: 6369250
Filing Date: 2002-04-09
Classification: C07C

Abstract:
A process for the preparation of a purified salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate having the formula: wherein R4 represents C5-C21 alkyl, C5-C21 alkyl, C5-C21 alkenyl, chlorinated C5-C21 alkyl or phenyl that can be substituted by 1 to 3 substituents from among the groups, F, Cl, SO3M, COOM, C1-C21 alkyl or C2-C20 alkenyl; R5 represents hydrogen or a C1-C3 alkyl; M represents hydrogen, ammonium, or an alkali metal atom such as sodium or potassium; n is an integer from about 1 to about 8; and comprising the steps of:(a) providing a source of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate; (b) admixing said source with a water-based purification system having water present at a ratio of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate to water ranging from 1:0.005 to 1:50; (c) separating a purified salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate from said purification mixture; and (d) collecting said purified salt of 4-sulfophenyl-[(1-oxyalkanoyl)amino]alkanoate.