ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Complexes of meso and racemic 2,3-diaminobutane-N,N,-N',N'-tetraacetic acid with alkaline earth metals

J. Majer and E. Dvořáková

Komensky University, Bratislava

Abstract: The complexes of these compds. with Ca²⁺, Mg²⁺, Sr²⁺, and Ba²⁺ were studied potentiometrically at 20° and ionic strength of 0.1M KCl. The following stability consts. are given. The dissocn. consts. (in pK units) were detd. as 1.8, 2.5, 6.27, and 11.2 for the meso acid and 2.4, 3.5, 6.12, and 11.7 for the racemic acid. meso acid, log KMHA, log KMA, racemic acid, log KMHA, log KMA; Ca²⁺, 2.7, 9.6, --, 12.3; Mg²⁺, 2.0, 8.8, --, 11.4; Sr²⁺, 1.8, 7.6, --, 10.2; Ba²⁺, 1.8, 6.5, --, 8.5; The differences in stability consts. of the complexes of both ligands were ascribed to the different steric arrangement of the N atoms and the COOH groups. The stability consts. measured were compared with those of the complexes of EDTA and diaminocyclohexane-N,N,N',N'-tetraacetic acids.

Full paper in Portable Document Format: 176a402.pdf (in Slovak)

Chemical Papers 17 (6) 402–410 (1963)