Supramolecular framework of a dinuclear cadmium complex with a dianion of xanthurenic acid [Cd2(Xan)2(H2O)4]

• Published in: Monatshefte für Chemie Vol. 143; no. 12; pp. 1643 - 1648
• Main Authors: Tratar Pirc, Elizabeta, Cer-Kerčmar, Ksenija, Modec, Barbara, Bukovec, Peter
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.12.2012
• Subjects: Analytical Chemistry; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Inorganic Chemistry; Organic Chemistry; Original Paper; Physical Chemistry; Theoretical and Computational Chemistry; Antioxidant activities; Carboxylic acids; Transition metal compounds; Crystal structure
• ISSN: 0026-9247; 1434-4475
• DOI: 10.1007/s00706-012-0855-9

Reaction of the sodium salt of xanthurenic acid (8-hydroxy-4-oxo-1 H -quinoline-2-carboxylic acid, H 2 Xan) with cadmium(II) cations in aqueous solution leads to the formation of the dinuclear complex [Cd 2 (Xan) 2 (H 2 O) 4 ]. The structure of this compound was studied by single-crystal X-ray diffraction, IR spectroscopy, and via thermal and elemental analysis. The [Cd 2 (Xan) 2 (H 2 O) 4 ] complex consists of two cadmium(II) ions bridged by a pair of carboxylate oxygen atoms from two Xan 2− ligands. The coordination environments of the two metal atoms are similar—each consists of two Xan 2− ligands and two aqua ligands. Each metal ion is in a pentagonal pyramidal coordination environment, which is highly unusual. An intricate pattern of hydrogen bonds links the molecules in the complex into a three-dimensional structure. Graphical abstract