Chiral complexes of PdCl₂ with hydroxypyrazolylquinoline and pyrazolylquinoline based on the monoterpenoid (+)-3-carene: Synthesis and structures

Abstract

The chiral complexes [PdL¹Cl₂] (I) and [PdL²Cl₂] (II) (where L¹ and L² are hydroxypyrazolylquinoline and pyrazolylquinoline, respectively, based on the monoterpenoid (+)-3-carene) were obtained and examined using X-ray diffraction. The crystal structures of complexes I and II are built from mononuclear acentric molecules. The Pd²⁺ ions coordinate two N atoms of the chelating bidentate ligand L¹ or L² and two Cl atoms. The coordination polyhedron Cl₂N₂ is a square distorted in a tetrahedral manner. In structure I, adjacent molecules are linked by intermolecular contacts and hydrogen bonds Cl···H-O, which gives rise to chains aligned with the axis x. In structure II, contacts that are substantially shorter than the van der Waals interactions were not detected.