Bis(μ-thiolato)-dicopper Containing Fully Spin Delocalized Mixed Valence Copper-Sulfur Clusters and Their Electronic Structural Properties with Relevance to the Cu A Site

With aromatic and aliphatic thiol-S donor Schiff base ligands, the copper-sulfur clusters, [(L1) Cu Cu ](ClO ) ·DMF·0.5CH OH ( ) and [(L2) Cu Cu (μ -S)(μ -O) ](ClO )·4H O, respectively, have been reported ( 2017, 53, 3334); HL1/HL2 are 2-(((3-methylthiophen-2-yl)methylene)amino)benzene/ethanethiol). Complex comprises a wheel shaped Cu S framework, made up of interlinked Cu {μ-S(R)} units. To understand the properties with relevance to the Cu site and to check whether self-assembly generates similar type clusters to , three complexes, [(L3) Cu Cu ](ClO ) ·(C H ) O·2.5H O ( ), [(L3 ) Cu Cu ](ClO ) ·1.25(C H ) O·1.25CH OH·2H O ( ), and [(L3 ) Cu Cu ](ClO ) ·2(C H ) O·H O ( ) have been synthesized with supporting ligands HL3 (HL3 = 2-((furan-2-ylmethylene)amino)benzenethiol when X = -H; X = -Cl or -CF to thiol-S are HL3 and HL3 ligands, respectively). The X-ray structures of and feature a similar Cu S architecture to . The spectroscopic properties and the X-ray structures revealed that - are fully spin delocalized mixed valence (MV) of type clusters. The structural parameters of the N Cu {μ-S(R)} units of and closely resemble those of the MV binuclear Cu site. With the aid of UV-vis-NIR, EPR, and spectroelectrochemical studies, the electronic properties of these complexes have been described in comparison with the MV model complexes and Cu site.