Isomeric molecular rectangles resulting from self-assembly of dicopper complexes of macrocyclic ligands

Dinuclear copper complexes containing hexaazacyclophane macrocyclic ligands react with the disodium salt of terephthalic acid resulting in the self-assembly of rectangular molecules with the general formula [(Cu2L)2(p-(O2-CC6H4CO2)2]X4, where X=CF3SO3 and ClO4. X-ray diffraction confirms their structure and ESI-MS analyses of solutions of the complexes exhibit cluster ions, which demonstrate that the cages are retained in solution.