New NiIICuIINiII and NiIICoIINiII trinuclear complexes with macrocyclic oxamido ligands

Abstract

New trinuclear complexes [Cu(NiL1)2(C2H5OH)2](ClO4)2 (1) and [Co(NiL2)2(H2O)2](ClO4)2 ·2(H2O) (2) were prepared using macrocyclic complex ligands with excess Cu(ClO4)2 · 6(H2O) and Co(ClO4)2 · 6(H2O), respectively, and characterized by X-ray crystallography. L1 and L2 denote the dianions of diethyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate and diethyl 5,6,7,8,15,16-hexahydro-15-methyl-6,7-dioxodibenzo[1,4,8,11]tetraazacyclotetradecine-13,18-dicarboxylate, respectively. In each complex, Ni(II) has the same distorted N4 square planar coordination. In 1, Cu(II) resides in a distorted octahedral O6 coordination environment, and the trinuclear cations are linked by oxamido–carbonyl interactions and π ··· π interactions involving unclosed π-systems to form 1-D supramolecular chains. In 2, Co(II) also resides in a distorted octahedral O6 coordination environment, while the trinuclear cations are linked by O–H ··· O hydrogen bonds and π ··· π interactions involving unclosed π-systems resulting in 1-D supramolecular chains.