Synthesis and structure of tris(dimethyldithiocarbamato) (1,10-phenanthroline)lanthanide complexes

Syntheses and structures of three new lanthanide coordination compounds with dithiocarbamate ligands are reported. The complexes [Ln(Me(2)dtc)(3)(phen)] (Ln = Pr (1), Nd (2) and Gd (3), Me(2)dtc = N,N-dimethyldithiocarbamate and phen = 1,10-phenanthroline) were synthetized by a simple metathesis between lanthanide(III) nitrate and sodium dimethyldithiocarbamate followed by addition of 1,10-phenanthroline without the exclusion of moisture. Single crystal X-ray analysis showed that all three complexes are isostructural, crystallizing in the triclinic space group P (1) over bar. The Ln-S and Ln-N bond lengths decrease in agreement with the decrease in ionic radii across the lanthanide series. Similar structures with Et(2)dtc ligands show no significant effect on the changes of Ln-S bond lengths and also on the S-Ln-S bite angles. The crystal packing of described complexes is formed via pi-pi stacking interactions and C-H center dot center dot center dot S non-covalent contacts.