Synthesis, Solid State, Solution and ESI‐MS Studies of Zinc(II) Cluster Complexes with a Branched Mixed Donor Thiolate Ligand

Abstract

Synthesis of the unusual spirobicyclic pentanuclear complex [Zn((ZnL)2(µ‐OH))2](ClO4)4·CH3CN·7H2O (1) (LH = N‐(2‐pyridylmethyl)‐N‐(2‐(methylthio)ethyl)‐N‐(2‐thioethyl)‐amine is described. Compound 1 was thoroughly characterized by a combination of X‐ray crystallography, XPRD, IR, variable temperature 1H NMR and ESI‐MS. The peripheral zinc ions of 1 have distorted trigonal bipyramidal coordination geometry provided by the NN′SS′ donor set of one L and a µ2‐hydroxido bridge to another peripheral zinc ion. The central zinc atom has a distorted tetrahedral Zn(SR)4 coordination environment provided by four µ2‐thiolate bridges from L. In crystalline form, the complex ions of 1 are largely insulated from contact by an elaborate hydrogen bond network involving µ2‐hydroxido bridges, perchlorate ions and all the solvent molecules. Dissociation of 1 in CD3CN solution and recombination to form other multinuclear complexes was investigated by variable temperature 1H NMR.