Macrocyclic Melamine‐Based Ligand Complexes as Building Blocks for the Metal‐Directed Synthesis of Heterometallic Di‐ and Trinuclear Compounds

Abstract

AbstractHeterodi‐ and heterotrimetallic NiII/CuII, Ni2II/CuII and NiII/Cu2II complexes of bis‐ and tris‐macrocyclic ligands, linked by a 1,3,5‐triazine spacer group, are obtained as products of copper(II)‐ or nickel(II)‐assisted condensations of the open‐chain tetraamine complexes [M2(2,3,2‐tet)]2+ [2,3,2‐tet= bis‐N,N′‐(2‐aminoethyl)propane‐1,3‐diamine, M2 = NiII or CuII] with formaldehyde and the monomacrocyclic ligand complexes [M1(L1)]2+, where L1 is a cyclam‐type macrocycle with a pendent melamine group (M1 = CuII or NiII). The spectroscopic (UV/Vis and EPR) and electrochemical properties of the oligonuclear heterometallic compounds in comparison with those of the homometallic analogues indicate small, but significant, intramolecular metal‐metal interactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)