Crystal Structure and Solution Fluxionality of Lanthanide Complexes of 2,4,6,-Tris-2-pyridyl-1,3,5-triazine

Abstract

The crystal structure of a europium chloride complex and of a praseodymium complex of 2,4,6,-tris(2-pyridyl)-1,3,5 triazine have been determined by single-crystal X-ray diffractometry. Two-dimensional proton NMR studies show for the complexes [Eu(tptz)X3] (X = Cl-, NO3-, OAc-) a fluxional motion of the metal around the three coordination sites of the ligand and indicate that the mechanism of this rotation is based on a complete dissociation of the metal.