Publication Date:
2011-06-16
Description:
A new copper(II) phosphonatobenzenesulfonate incorporating 4,4′-bipyridine (4,4′- bipy ) as auxiliary ligand has been discovered through systematic high-throughput (HT) screening of the system Cu(NO 3 ) 2 ·3H 2 O/H 2 O 3 PC 6 H 4 SO 3 H/4,4′- bipy using different solvents. The hydrothermal synthesis of [Cu(HO 3 PC 6 H 4 SO 3 )(C 10 H 8 N 2 )]·H 2 O ( 1 ) was further optimized by screening various copper(II) salts. The crystal structure of 1 was determined by single-crystal X-ray diffraction and unveiled the presence of isolated sixfold coordinated Jahn–Teller-distorted Cu 2+ ions. The isolated CuN 2 O 4 octahedra are interconnected by phosphonate and sulfonate groups to form chains along the c- axis. The organic groups, namely phenyl rings and 4,4′- bipy molecules cross-link the chains into a three-dimensional framework. Water molecules are found in the narrow voids in the structure which are held by weak hydrogen bonds. Upon dehydration, the structure of 1 undergoes a phase transition, which was confirmed by TG measurements and temperature dependent X-ray powder diffraction. The new structure of 1-h was refined with Rietveld methods. Detailed inspection of the structure revealed the directional switching of the Jahn–Teller distortion upon de/rehydration. Weak ferro-/ferrimagnetic interactions were observed by magnetic investigations of 1 , which switch to antiferromagnetic below 3.5 K. Compounds 1 and 1-h are further characterized by thermogravimetric and elemental analysis as well as IR spectroscopy.
Print ISSN:
0044-2313
Electronic ISSN:
1521-3749
Topics:
Chemistry and Pharmacology
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