Unprecedented Fluorescent Dinuclear Co(II) and Zn(II) Coordination Compounds with a Symmetric Bis(salamo)-Like Tetraoxime

Two unprecedented homometallic Co(II) and Zn(II) coordination compounds, [M(2)(L)(OCH(3))][M(2)(L)(OAc)] (M(II) = Co(II) (1) and Zn(II) (2)), with a novel symmetric bis(salamo)-like tetraoxime ligand H(3)L were synthesized and characterized by elemental analyses, infrafred (IR), ultraviolet–visible spectroscopy (UV-Vis), fluorescent spectra and single-crystal X-ray diffraction analyses. The unit cell of the two coordination compounds contains two crystallographically and chemically independent dinuclear coordination compounds. In the two coordination compounds, three metal ions are five-coordinated, formed two square pyramidal and a trigonal bipyramidal geometries, and the other metal ion is a hexacoordinate octahedral configuration. In addition, the coordination compound 1 forms a 3D supramolecular structure, and the coordination compound 2 forms a 0D dimer structure by the inter-molecular hydrogen bond interactions. Meanwhile, the fluorescence spectra of the coordination compounds 1 and 2 were also measured and discussed.