Six-membered ring chelate complexes of Pd(II) and Pt(II) derived from di-(2-pyridyl)pyrimidin-2-ylsulfanylmethane

Cis-[MLCl2] complexes of di-(2-pyridyl)pyrimidin-2-ylsulfanylmethane ligand (L), where M = Pd (1), and M = Pt (2) have been synthesized. Reaction of 1 with L in presence of Na[BF4] and hot acetonitrile produced the complex [PdL2](BF4)2 (3). Complexes 1–3 and ligand L have been characterized by elemental analyses, IR and NMR spectroscopy. Crystal structures of 1, 3 and L were determined by single crystal X-ray diffraction analyses, showing nonplanar structures with the pyridinic rings twisted around the bridging carbon and the ipso carbon bonds. 1 and 3 displayed a bidentate coordination of L to the palladium atom with the formation of six-membered chelate rings, where the local geometry at palladium atom was distorted square planar. In 3 the palladium atom was coordinated to two dipyridyl ligands through two of the pyridinic nitrogen atoms to form a cationic complex stabilized by two tetrafluoroborate counter-ions.

Synthesis of the cis-[MLCl2] complexes derived from di-(2-pyridyl)pyrimidin-2-ylsulfanylmethane ligand (L), where M = Pd (1), and M = Pt (2) is described. The formation of the [PdL2](BF4)2 complex (3) from the reaction of 1 with Na[BF4] and L in hot acetonitrile, is also reported. Crystal structures of 1 and 3 showed a bidentate coordination mode of the ligand L to the palladium atom with the formation of six-membered chelate rings.Figure optionsDownload as PowerPoint slideHighlights
► We describe the coordinative behavior of a novel dipyridyl ligand.
► The ligand displayed a bidentate coordination mode toward Pd(II) and Pt(II).
► The pyrimidin-2-yl group is mainly in a flagpole position.
► The major conformer was identified by NMR and X-ray diffraction.