Structural Characterization of the First Example of a Bis(.mu.-thiolato)dicopper(II) Complex. Relevance to Proposals for the Electron Transfer Sites in Cytochrome c Oxidase and Nitrous Oxide Reductase

Despite its prevalence in transition metal chemistry in general, to our knowledge the doubly-bridged M{sub 2}({mu}-SR){sub 2} motif is unknown for M = Cu(II), presumably because of the tendency for operation of eq 2Cu(II) + 2SR{sup -1} {yields} 2Cu(I) + RSSR, for which the appropriate stoichiometry would be provided in attempted assembly reactions. Herein we report the use of a new, sterically hindered ligand for the isolation of the first example of such a complex, which has been subjected to structural investigations oriented toward relating its properties to those of the CcO and N{sub 2}OR electron transfer sites. 21 refs., 2 figs.