title: Synthesis, ESR, UV-Visible and reactivity studies of new bis(N-dimethoxyaniline-3,5-(t)Bu2-salicylaldiminato)copper(II) complexes.
abstract: Several new copper(II) complexes (4-6) with N-dimethoxyphenyl-3,5-(t)Bu(2)-salicylaldimine ligands abbreviated as N-R-3,5-DTBS, where R=2,4-dimethoxyphenyl (1), 2,5-dimethoxyphenyl (2) and 3,5-dimethoxyphenyl (3) have been prepared and their spectroscopic (IR, (1)H NMR, UV/Vis, ESR), magnetic and redox reactivity are described. The ESR spectra of frozen-solution 4-6 and solid state 4 and 5 are indicative of axially symmetric g-tensor (g([parallel])>g([perpendicular])>2.03). The powder ESR spectrum of 6 is unusual for CuN(2)O(2) type systems and exhibits "reversed" type (g([parallel])<g([perpendicular])) signal with a rhombic g-tensor g(3) (2.235)>g(2) (2.128)>g(1) (2.019) pattern indicative of a d(z)(2) ground state. Chemical oxidation of 4 and 6, as supported by ESR and UV/Vis techniques, generates new Cu(II) species and Cu(II)-phenoxyl radicals. The CV studies have shown that the complexes possess ligand-centered and copper(II)-centered quasi-reversible and irreversible responses.
authors.affiliation: Department of Chemistry, Harran University, 63300 Sanlıurfa, Turkey. vkasumov@harran.edu.tr
authors.forename: Veli T
authors.initials: VT
authors.lastname: Kasumov
authors.forename: Fevzi
authors.initials: F
authors.lastname: Köksal
mesh_terms: D000814:Aniline Compounds / Q000138:chemical synthesis / Q000737:chemistry; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D009682:Magnetic Resonance Spectroscopy; D010084:Oxidation-Reduction; D010636:Phenols / Q000138:chemical synthesis / Q000737:chemistry*; D012457:Salicylamides; D020156:Salicylic Acid / Q000138:chemical synthesis / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000814:Aniline Compounds; D056831:Coordination Complexes; D010636:Phenols; D012457:Salicylamides; C042329:phenoxy radical; D003300:Copper; D020156:Salicylic Acid