Thermodynamics of the CuII μ-Thiolate and CuI Disulfide Equilibrium: A Combined Experimental and Theoretical Study
摘要:
The redox equilibrium between dinuclear Cu-II mu-thiolate and Cu-I disulfide structures has been analyzed experimentally and via DFT calculations. Two new ligands, (LSSL2)-S-2 and (LSSL4)-S-4, and their Cu-II mu-thiolate and Cu-I disulfide complexes were synthesized. For (LSSL2)-S-2, these two redoxisomeric copper species are shown to be in equilibrium, which depends on both temperature and solvent. For (LSSL4)-S-4 the mu-thiolate species forms as the kinetic product and further evolves into the disulfide complex under thermodynamic control, which creates the unprecedented possibility to both species under the same reaction conditions. The energies of the mu-thiolate and disulfide complexes for two series of related ligands have been calculated with DFT; the results rationalize the experimentally observed structures, and emphasize the important role that steric requirements play in the formation of the Cull thiolate structure.
Interconversion between Bis(<i>μ</i>-thiolato)dicopper(II) and Disulfide-Bridged Dicopper(I) Complexes Mediated by Chloride Ion
作者:Yoshiki Ueno、Yoshimitsu Tachi、Shinobu Itoh
DOI:10.1021/ja027397m
日期:2002.10.1
An unprecedented clean interconversion between a novel bis(mu-thiolato)dicopper(II) complex (1) and a disulfide-bridged dicopper(I) complex (3) through a disulfide-bridged (mu-chloro)dicopper(I) complex (2) mediated by chlorideion has been established for the first time, providing a new redox chemistry of the transition metal-sulfur complexes. Crystal structures of 1 and 3 as well as spectroscopic
Disulphide bond cleavage in a pyridine-containing disulphide–copper(<scp>II</scp>) system under aerobic conditions. X-Ray crystal structure analysis of the product, diaquabis{µ-2-[(2-pyridymethyl)-amino]ethylsulphinato-O}dicopper(<scp>II</scp>) dichloride
The diaulphide bond in a pyridine-containingdisulphide was cleavage in the presence of copper(II) and dioxygen to give the copper(II) complex of the corresponding sulphinate, whose X-raycrystalstructureanalysis has disclosed a dimeric structure with the sulphinate oxygen atom bridging the copper(II) ions in a square-pyramidal environment.