Trinuclear Cu(II) capsules self-assembled by nitrilotripropionate

Five trinuclear copper(II) complexes supported by nitrilotripropionate (ntp) have been prepared at acidic pH values and characterized by elemental, infrared and X-ray diffraction methods. The structure of the polynuclear complexes show the presence of well-defined capsules formed by three Cu(II) cations and two protonated Hntp ligands in a tritopic arrangement. The counter ion of the copper salt used in the preparation influences the final structure, by changing the connection between the capsules.