Synthesis and Characterization of Polynuclear Copper(II) Complexes with Pyridylbis(phenol) Ligands

Three new pyridylbis(phenol) ligands with imine (H2Limine), amine (H2Lamine), or amide (H4Lamide) linkages, along with their copper complexes, were synthesized and characterized. Treatment of H2Limine with copper(II) in the presence of base produced mononuclear copper complex [Cu(Limine)(MeOH)] (1), while the same procedure with H2Lamine produced trinuclear [Cu3(Lamine)2(CH3CN)2](ClO4)2 (2). The more rigid H4Lamide forms tetranuclear [Cu4(Lamide)2(H2O)4] (3), which upon recrystallization yielded crystals of hexanuclear [Cu6(HLamide)4(H2O)2] (4).