Synthesis, crystal structure and properties of two macrocyclic dinuclear complexes

Two macrocyclic dinuclear complexes, [Cu2L1](PF6)2 and [Cu2L2](ClO4)2, were synthesized by cyclo-condensation between N,N′-bis(3-formyl-5-methylsalicylidene)ethylenediimine or N,N′- bis(3-formyl-5-n-butylsalicylidene)ethylenediimine and ethylenediamine in the presence of Cu2+ ions. The crystal structures of the complexes were studied. The variable-temperature magnetic susceptibilities and cyclic voltammograms of the complexes were measured. The magnetic and electrochemical properties of the complexes were discussed. The results show that the complexes display very strong antiferromagnetic exchanges and that all copper(II) complexes undergo a one-electron transfer process.