Synthesis, structural, spectroscopic and magnetic susceptibility studies of a soluble Cr(III)-heida (2-hydroxyethyliminodiacetic acid) complex. Relevance to aqueous chromium(III)-heida speciation

Aqueous reaction of Cr(III) with 2-hydroxyethyliminodiacetic acid (heida) at pH 5.5 led to the synthesis and isolation of a new complex (NH4)[Cr{HOCH2CH2N(CH2COO)2}2] · 2H2O (1). Compound 1 was characterized by analytical, spectroscopic (UV-Vis, FT-IR, EPR) techniques, magnetic susceptibility, thermal studies, and X-ray crystallography. The mononuclear, octahedral pH-variant contains two symmetrically bound ligands. The collective physicochemical properties of 1 formulate its profile and project Cr(III) interactions with low molecular mass physiological ligands in biologically relevant cellular events.