Synthesis, characterization, single crystal X-ray structure, EPR and theoretical studies of a new hybrid inorganic-organic compound [Cu(Hdien)(2)(H2O)(2)](Pnb)(4)center dot 4H(2)O and its structural comparison with related [Cu(en)(2)(H2O)(2)](pnb)(2)

摘要

A new hybrid inorganic-organic compound [Cu(Hdien)(2)(H2O)(2)](pnb)(4)center dot 4H(2)O (1) (where pnb = p-nitro benzoate), in which the tridentate ligand diethylenetriamine (dien) shows an unusual coordination behavior acting as a bidentate ligand when present in its monoprotonated form (Hdien(+)) has been synthesized by the reaction of copper(II) p-nitrobenzoate and slight excess of dien in methanol-water mixture (4:1v/v). Re-crystallization of the violet precipitated product from hot water gave single crystals suitable for X-ray diffraction studies. The newly synthesized compound 1 has been characterized by spectroscopic techniques (UV Vis, EPR), and theoretical methods (DR' and MRCI/SORCI). Single crystal X-ray structure determination revealed the existence of the cationic species Ku(Hdien)(2)(H2O)(2)](4+), four p-nitrobenzoate as counter anions and four water molecules are present as solvent of crystallization. Packing analyses of title compound as well as of the structurally similar [Cu(en)(2)(H2O)(2)](pnb)(2), 2 has shown similarities in the crystalline architecture that both hybrid inorganic-organic compounds is stabilized by various non-covalent interactions such as N-H center dot center dot center dot O, C-H center dot center dot center dot O, O-H center dot center dot center dot O etc. (C) 2016 Elsevier B.V. All rights reserved.