title: The trivalent copper complex of a conjugated bis-dithiocarbazate Schiff base: stabilization of Cu in three different oxidation states.
abstract: The new tribasic N(2)S(2) ligand H(3)ttfasbz has been synthesized by condensation of 4-thenoyl 2,2,2-trifluoroacetone and S-benzyl dithiocarbazate. On complexation with copper(II) acetate, spontaneous oxidation to the Cu(III) oxidation state is observed, and the complex [Cu(ttfasbz)] has been isolated and characterized structurally. Reduction to the EPR active Cu(II) analogue has been achieved chemically and also electrochemically, and in both cases, the process is totally reversible. The Cu(III/II) redox potential of the complex is remarkably low and similar to that of the ferrocenium/ferrocene couple. Further reduction to the formally monovalent (d(10)) dianion [Cu(I)(ttfasbz)](2-) may be achieved electrochemically. Computational chemistry demonstrates that the three redox states [Cu(ttfasbz)], [Cu(ttfasbz)](-), and [Cu(ttfasbz)](2-) are truly Cu(III), Cu(II), and Cu(I) complexes, respectively, and the potentially noninnocent ligand does not undergo any redox reactions.
authors: Chemistry Programme, Faculty of Science, Universiti Brunei Darussalam, BE 1410, Brunei Darussalam.
authors: Mohammad
authors: M
authors: Akbar Ali
authors: Paul V
authors: PV
authors: Bernhardt
authors: Mathilde A H
authors: MA
authors: Brax
authors: Jason
authors: J
authors: England
authors: Anthony J
authors: AJ
authors: Farlow
authors: Graeme R
authors: GR
authors: Hanson
authors: Lee Len
authors: LL
authors: Yeng
authors: Aminul Huq
authors: AH
authors: Mirza
authors: Karl
authors: K
authors: Wieghardt
mesh_terms: D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006834:Hydrazines / Q000737:chemistry*; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010084:Oxidation-Reduction; D011789:Quantum Theory; D012545:Schiff Bases / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D006834:Hydrazines; D008024:Ligands; D009942:Organometallic Compounds; D012545:Schiff Bases; D013438:Sulfhydryl Compounds; C010877:carbazic acid; D003300:Copper