Process for the preparation of polyaminocarboxylic acids and chelate compounds thereof

Abstract

The present invention relates to a process for the preparation of polyaminocarboxylic acids, in particular phenolic aryl- or alkyldiaminepolycarboxylic acids, preferably a compound of formula (I): wherein X is selected from the group consisting of: H, COOH, COO−Y+, OH, linear or branched C1-C5 alkyl, CH2OH, SO3H, SO3−Y+, wherein: —Y+ is independently selected from the group consisting of: Li+, Na+, K+, and NH4+; and wherein A is selected from: —A (CH2)n linear aliphatic system, wherein n=2, 3 or 4, preferably 2 or 3; and —an aromatic system of formula (II): wherein R1, R2 are independently selected from the group consisting of H, OH, and linear or branched C1-C5 alkyl; said process comprising the step of reacting, a phenol compound, glyoxylic acid and an aryl- or alkyldiamine in the presence of an iron source to obtain a reaction mixture comprising the compound of formula (I). The invention also relates to a process for the preparation of a chelate compound, which is a complex of the compound of formula (I) with iron.

Dependencies are inferred from the claim text.