Structural characterization and DFT study of bis-{()-2-[(2-hy-droxy-benz-yl)amino]-3-(4-hy-droxy-phen-yl)propano-ato-κ,}(1,10-phenanthroline-κ,')cadmium(II) tetra-hydrate.

In the title compound, [Cd(CHO)(CHN)]·4HO, the Cd ion lies on a twofold rotation axis and is chelated by two monodeprotonated residues of the l-tyrosine-derived ligand ()-2-[(2-hy-droxy-benz-yl)amino]-3-(4-hy-droxy-phen-yl)propanoic acid () in a κ, amino acid chelating mode, exhibiting an (,')- disposition, and by 1,10-phenanthroline in a κ,' mode. The latter ligand is also located about the twofold rotation axis that bisects the central six-members ring. The phenolic groups remain protonated and non-coordinating and take part as acceptors in the intra-molecular hydrogen bonds with the amino groups of the acido ligands. The Cd ion is six-coordinated in a distorted octa-hedral environment. In the crystal, O-H⋯O hydrogen bonds result in the formation of three-dimensional network structures. The title complex has also been characterized by IR and H NMR spectroscopy and DFT studies. The crystal studied was refined as an inversion twin.