Crystal structure of two binuclear Cu2+ complexes with 1,4,7,10-tetra-azacyclododecane-N,N′,N″,N‴-tetra-acetic acid and 1,4,8,11-tetra-azacyclotetradencane-N,N′,N″,N‴-tetra-acetic acid

Abstract

The structure of the binuclear Cu²⁺ complexes with the two title ligands are unexpected and completely different from each other, the 14-membered macrocycle giving a true binuclear species with two nearly identical Cu²⁺–macrocycle units, whereas the 12-membered ligands one Cu²⁺ through the four nitrogens of the macrocycle and two carboxylates and the other one only through carboxylates with a similar structure to that found in many dicopper(II) tetracarboxylate systems.