Synthesis, characterization and luminescent properties of polymeric cadmium(II) bridged-thiocyanato and mononuclear thiocyanato-zinc(II) complexes of pyridine-N-oxide derivatives

The synthesis and structural characterization of six new d10 Cd(II) and Zn(II) thiocyanato complexes with pyridine-N-oxide compounds: the polymeric catena-[Cd(μ2-2-picoline-N-oxide)(μN,S-NCS)2] (1), catena-[Cd(μ2-3-picoline-N-oxide)(μN,S-NCS)2] (2), catena-[Cd(4-nitropyridine-N-oxide)2(μN,S-NCS)2] (3), the dinuclear [Cd(4-cyanopyridine-N-oxide)2(μN,S-NCS)(NCS)(H2O)]2 (4) and the mononuclear complexes [Zn(2-picoline-N-oxide)2(NCS)2(H2O)] (5) and [Zn(4-cyanopyridine-N-oxide)2(NCS)2(H2O)] (6) are reported. Single crystal X-ray crystallography revealed the 2D polymeric nature in complexes 1 and 2, the 1D chain in 3 and the dimeric structure in complex 4 with the doubly-bridged Cd(μN,S-NCS)2Cd moiety. Five-coordinate monomeric Zn(II) complexes were obtained in 5 and 6, where the thiocyanto ligands are acting as monodentate N-bonded. The emission spectral properties of the six complexes were investigated. Very strong enhancing fluorescence intensity was observed in complex 3.

Graphical abstractA novel series of thiocyanato polymeric Cd(II) and mononuclear Zn(II) complexes based on pyridine-N-oxide compounds were synthesized and their emission spectral properties were investigated.Figure optionsDownload full-size imageDownload as PowerPoint slide