title: Copper(II) complexes of N-(2-{[(2E)-2-(2-Hydroxy-(5-substituted)-benzylidene)-hydrazino]carbonyl}phenyl)benzamide ligands and heterocyclic coligands.
abstract: Some copper(II) complexes of the type [Cu(L1-3)(phen]·CH2Cl2 (1a-3a) and [Cu(L1-3) (bipy)]·CH2Cl2 (1b-3b) (where L1=N-(2-{[(2E)-2-(2-Hydroxy-benzylidene)-hydrazino]carbonyl}phenyl)benzamide, L2=N-(2-{[(2E)-2-(2-Hydroxy-(5-bromo)-benzylidene)-hydrazino]carbonyl}phenyl)benzamide, L3=N-(2-{[(2E)-2-(2-Hydroxy-(5-methoxy)-benzylidene)-hydrazino]carbonyl}phenyl)benzamide; phen=1,10-phenanthroline, bipy=2,2'-bipyridine) have been prepared and characterized on the basis of elemental analyses, IR, UV-Vis and EPR spectral studies. IR spectra indicate that the ligand L1-3 exists in the keto form in the solid state, while at the time of complexation, it tautomerises into enol form. The single crystal X-ray diffraction study of the representative complex [Cu(L1) (phen)]·CH2Cl2 (1a) reveals the distorted square pyramidal geometry around copper(II). Crystal data of (1a): space group=P21/n, a=11.5691(16) Å, b=11.0885(15) Å, c=24.890(4) Å, V=3166.2(8) Å(3), Z=4. The electrochemical behavior of all the complexes indicate that the phen complexes appears at more positive potential as compared to those for bipy complexes, as a consequence of its stronger π acidic character. All the complexes exhibit blue-green emission as a result of the fluorescence from the intra-ligand (π→π(*)) emission excited state.
authors.affiliation: Department of Chemistry, Shivaji University, Kolhapur 416004, MS, India. Electronic address: sanjaycha2@rediffmail.com.
authors.forename: S S
authors.initials: SS
authors.lastname: Chavan
authors.forename: V A
authors.initials: VA
authors.lastname: Sawant
authors.forename: A N
authors.initials: AN
authors.lastname: Jadhav
mesh_terms: D001549:Benzamides / Q000737:chemistry*; D056831:Coordination Complexes / Q000737:chemistry* / Q000378:metabolism; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D004578:Electron Spin Resonance Spectroscopy; D005453:Fluorescence; D006571:Heterocyclic Compounds / Q000737:chemistry* / Q000378:metabolism; D008024:Ligands; D008956:Models, Chemical; D015394:Molecular Structure; D010618:Phenanthrolines / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001549:Benzamides; D056831:Coordination Complexes; D006571:Heterocyclic Compounds; D008024:Ligands; D010618:Phenanthrolines; C037689:benzamide; D003300:Copper; C025205:1,10-phenanthroline
keywords: Copper(II) complexes; Cyclic voltammetry; EPR spectra; Hydrazone derivatives; X-ray crystal structure