Ethylenediamine disuccinic acid

Structural formula
Structural formula without stereochemistry
General
Surname	Ethylenediamine disuccinic acid
other names	EDDS Ethylene diamine disuccinate
Molecular formula	C 10 H 16 N 2 O 8
External identifiers / databases
CAS number 20846-91-7 178949-82-1 (as trisodium salt) PubChem 123395 ChemSpider 109992 Wikidata Q412231
properties
Molar mass	292.24 g mol −1
Physical state	firmly
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Ethylenediamine disuccinic acid (ethylenediamine disuccinate , abbreviated to EDDS) is a multidentate ligand and a chelate complex former. It has a similar chemical structure and properties to EDTA .

Isomerism

Ethylenediamine disuccinic acid has two stereocenters , so it occurs in three different stereoisomers :

• ( S , S ) -EDDS,
• ( R , R ) -EDDS and
• meso -EDDS [( R , S ) -EDDS].

Occurrence

( S , S ) -EDDS occurs naturally in various actinomycetes .

Extraction and presentation

The addition of ethylenediamine to maleic acid represents a simple and easily feasible access to EDDS on a large industrial scale . In this way, however, a stereoisomeric mixture is obtained which consists of equal parts of the ( S , S ) and the ( R , R ) isomers and also the ( R , S ) isomer (= meso form).

A targeted, but more expensive synthesis for ( S , S ) -EDDS consists in the reaction of L - aspartic acid with 1,2-dibromoethane .

use

EDDS serves as a replacement for EDTA. The complex formation constants for the chelate complexes with metal ions are usually only slightly smaller than those of EDTA, so that it could largely substitute it. The areas of application are the same as those of EDTA, e.g. B.

• Additive to cleaning agents (water softening by binding Ca ²⁺ / Mg ²⁺ ),
• Complexation of heavy metal ions,
• Soil washing of heavy metal contaminated earth.

( S , S ) -EDDS is easily and completely biodegradable, meso -EDDS is partially biodegradable; the problem is the ( R , R ) stereoisomer, which persists in the environment. Nevertheless, EDDS appears to be an at least partially biodegradable replacement for the comparatively extremely long-lived EDTA. The ( S , S ) -stereoisomer is a derivative of the natural amino acid L - aspartic acid [( S ) -aspartic acid] - this is also the reason for its good biodegradability .

Individual evidence

1. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
2. ↑ Michel Barbier, Daria Bogdanovsky, Walter Vetter, Edgar Lederer: Synthesis and properties of an analog of Lycomarasmin and Aspergillomarasmine. In: Justus Liebig's Annals of Chemistry. 668, 1963, p. 132, doi : 10.1002 / jlac.19636680115 .
3. ↑ D. Schowanek, TC Feijtel, CM Perkins, FA Hartman, TW Federle, RJ Larson: Biodegradation of [S, S], [R, R] and mixed stereoisomers of ethylene diamine disuccinic acid (EDDS), a transition metal chelator. In: Chemosphere Volume 34, Number 11, June 1997, pp. 2375-2391, PMID 9192467 .
4. ↑ PC Vandevivere, H. Saveyn, W. Verstraete, TC Feijtel, DR Schowanek: Biodegradation of metal- [S, S] -EDDS complexes. In: Environmental Science & Technology Volume 35, Number 9, May 2001, pp. 1765-1770, PMID 11355190 .
5. ↑ TC Yip, DC Tsang, KT Ng, IM Lo: Kinetic interactions of EDDS with soils. 1. Metal absorption and competition under EDDS deficiency. In: Environmental Science & Technology Volume 43, Number 3, February 2009, pp. 831-836, PMID 19245023 .