To economically product the subject high-purity compound, useful as a builder for detergents and excellent in chelating ability in high yield at a low cost by carrying out the oxidizing dehydrogenating reaction of a hydroxyaminocarboxylic acid, etc., in the presence of an alkali metallic hydroxide, water and a copper-containing catalyst.
The oxidizing dehydrogenating reaction of a hydroxyaminocarboxylic acid or its salt represented by formula I [R1 and R2 are each H or (CH2)nCOOM [M is H, an alkali metal, etc.; (m) is 1-6] is carried out in the presence of an alkali metallic hydroxide, e.g. NaOH or KOH, water and a copper-containing catalyst, e.g. metallic copper or a developed Raney copper to afford an amino-ethercarboxylic acid or its salt represented by formula II. The amount of the alkali metallic hydroxide is an equiv. amount of 0.9-2.0 times based on OH groups in the compound represented by formula I and the amounts of the water and catalyst are ≥50wt.% and 1-50wt.% based on the compound represented by formula I. The produced H is removed by usually keeping the reactional temperature at 150-260°C and the reactional pressure at 8-30kg/cm2G.
DANJO HIROSHI
NISHIMOTO YOSHIFUMI
