Metal Complexes in Biology and Medicine, V. — New Bismuth Hydroxycarboxylate Complexes. Synthesis and Structure of Bismuth(III) Malate Monohydrate and Bismuth(III) Tartrate Trihydrate
Reaction of Bi(NO3)3 · 5 H2O with L-(–)-malic acid results in the formation of bismuth(III) malate monohydrate Bi[O2CCH2CH(O)CO2] · H2O (1) containing the tridentate ligand [L-(–)-malate]3– with all donating functions deprotonated. By way of contrast, reaction of Bi(NO3)3 · 5 H2O with L-(+)-tartraic acid gives bismuth(III) tartrate trihydrate (2), in which two different tartrate ligands, [L-(+)-tartrate]1– and [L-(+)-tartrate]2– are present. The solid-state structures have been determined by single-crystal X-ray methods and confirmed by powder diffraction measurements. The structure analyses exhibit a three-dimensional network in the crystalline state resulting from bridging and chelating properties of the polydentate hydroxycarboxylate ligands. Bismuth shows high coordination numbers.