Synthesis, crystal structures, luminescence properties and catalytic application of lanthanide(III) piperidine dithiocarbamate complexes

A series of lanthanide(III) piperidine dithiocarbamate complexes [Ln(Pip-Dtc)(3)(Phen)] [where Ln = La(III), Ce(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III), Dy(III), Er(III); Pip-Dtc = piperidine dithiocarbamate and Phen = 1,10-phenanthroline] has been synthesized and structurally characterized by analytical and various spectral techniques such as FT-IR, UV-Vis and H-1 NMR. The molecular structure of [Pr(Pip-Dtc)(3)(Phen)], [Nd(Pip-Dtc)(3)(Phen)] and [Sm(Pip-Dtc)(3)(Phen)] complexes were determined by single crystal X-ray diffraction studies. The binding of the Pip-Dtc to the metal center involves two sulfur atoms and Phen through two nitrogen atoms. The metal center is octa-coordinated by three Pip-Dtc and one Phen ligands. The coordination geometry around Ln(III) ion is distorted dodecahedron. The photoluminescence properties of Sm(III), Pr(III), Tb(III), Dy(III) complexes indicated that the emission intensity depend on the nature of the metal ion, ligand and polarity of the medium. These complexes exhibited good to excellent catalytic activity in trimethylsilyl cyanation of benzaldehyde. (C) 2015 Elsevier Ltd. All rights reserved.