Coordinating behaviour of a new pyridylhydrazone; tris-complexes of manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) with 2-pyridylcarbaldehyde- N, N-dimethylhydrazone.

The preparation and characterization of tris-complexes of Mn, Co, Ni, Cu and Zn with a new pyridylhydrazone, 2-pyridylcarbaldehyde- N, N-dimethylhydrazone (pch), are described. In all the complexes pch behaves as a bidentate ligand binding through the pyridine and azomethyne nitrogen atoms. The complexes appear to be monomeric, high spin six-coordinate, and a distorted octahedral stereochemistry around the metal is suggested. The e.p.r. results for both Cu compounds indicate a mainly d−y ground state with a static Jahn-Teller distortion, whilst for the Mn complex the e.p.r. data indicates a very low symmetry for the MnN polyhedron. [ABSTRACT FROM AUTHOR]