A novel anagostic C-H•••Cu interaction and clustered water molecules in copper(II)-pyridine-2,5-dicarboxylate complex

In this study, a new mononuclear Cu(II)-pyridine-2,5-dicarboxylate complex with N,N-diethylethylenediamine (deen), [Cu(pydc)(deen)(H2O)]center dot 2H(2)O (1) (pydc = pyridine-2,5-dicarboxylic acid or isocinchomeronic acid), has been synthesized. Elemental, thermal analysis and IR spectroscopic study have been performed to characterize the complex. The molecular structure of the complex has been determined by single crystal X-ray diffraction. In 1, the Cu(II) ion is coordinated by pyridine nitrogen and carboxylate oxygen atoms from pydc. The square pyramidal geometry around Cu(II) is completed by two N atoms from deen and aqua ligands. One of the interesting structural features of 1 is the presence of obvious C-H center dot center dot center dot M anagostic interactions between the Cu(II) ion and the H atom of ethyl group. (C) 2011 Elsevier By. All rights reserved.