Synthesis and structural and magnetic properties of mononuclear, dinuclear, and tetranuclear copper(II) complexes of a 17-membered macrocyclic ligand (HM3), capable of forming endogenous phenoxide and pyridazino bridges: X-ray crystal structures of (Cu2(M3)(mu2-OMe)(NO3)2), (Cu4(M3)2(mu3-OMe)2(mu2-Cl)2Cl2), (Cu4(M3)2(mu3-OEt)2(mu2-N3)2)(MeOH), (Cu4(M3)2(mu3-OMe)2(NCS)4)(DMF), and (Cu(M3))

A binuclear copper(II) complex of the 17-membered macrocyclic ligand HM3 is formed by template condensation of 2,6-diformyl-4-methylphenol with PTA in the presence of copper(II) nitrate and trifluoromethanesulfonate. Cu2(M3)(mu2-OMe)(NO3)2 produces tetranuclear Cu(II) derivatives on treatment with chloride, azide, thiocyanate and bromide. Cu(II) complexes have phenoxide and methoxide bridges between the two Cu centers, and exhibit antiferromagnetic coupling properties.