Received 26 September 2010
The hydrothermal reaction of cadmium(II) nitrate with 5-amino-2,4,6-triiodoisophthalic acid and pyridine in DMF solution leads to the formation of the title compound, [Cd(C8H2I3NO4)(C5H5N)2]n. The structure contains a four-coordinate Cd2+ ion in a distorted tetrahedral geometry, which lies on a crystallographic twofold rotation axis. The Cd2+ ion is bonded to two N atoms from two pyridine ligands and two carboxylate O atoms from two 5-amino-2,4,6-triiodoisophthalate anions. The Cd-O distances are 2.429 (5) and 2.305 (5) Å and the Cd-N distance is 2.236 (8) Å. The two carboxylate groups of individual 5-amino-2,4,6-triiodoisophthalate anions act as a bridge to the Cd2+ atoms. leading to a chain structure along the c axis.
For the isotypic Hg complex, see: Zhang et al. (2008). For the structure of 5-amino-2,4,6-triiodoisophthalic acid monohydrate, see: Beck & Sheldrick (2008). For the structures of related metal complexes, see: Dai et al. (2008)·For the use of triiodinated aromatic compounds in radiology, see: Estep et al. (2000).
Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 2000); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SI2296 ).
The author thanks the Natural Science Foundation of Zhejiang Province, China (No. Y4080342) and the Science Foundation of Zhejiang Sci-Tech University (No. 0813622-Y) for financial support.
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