Specific transport of copper(II) ions across a liquid membrane mediated by a lipophilic tetraaza macrocycle

The lipophilic diamine-diamide macrocycle 13-hexadecyl-1,4,8,11-tetraazacyclotetradeca-12,14-dione transports Cu2+ ions across a bulk CH2Cl2 membrane from a neutral aq. source phase to an acidic aq. receiving phase. The flow of Cu2+ ions is coupled to a counterflow of protons due to a deprotonation/protonation mechanism of the macrocycle amido groups, assocd. to the Cu2+ incorporation/demetalation process. The pH driven transport process is specific for Cu and its rate is independent of the presence of other metal ions in the source phase.