Competitive bulk liquid membranetransport and solvent extraction of some metal ions using RC(S)NHP(X)(OiPr)2 (X = O, S) as ionophores. Formation of the polynuclear complex of [Ag(NC–NP(S)(OiPr)2)]n

Abstract

Competitive transport experiments involving metal ions from an aqueous source phase through a chloroform membrane into an aqueous receiving phase have been carried out using a series of N-(thio)phosphorylated (thio)amide and thiourea ligands as the ionophore present in the organic phase. The source phase contained equimolar concentrations of Co^II, Ni^II, Cu^II, Zn^II, Ag^I, Cd^II and Pb^II with the source and receiving phases being buffered at a number of different pHs. Solvent extraction properties of the ligands towards the same metal cations under the same experimental conditions as for the transport were also studied. All ligands demonstrated 100% extraction of Ag^I. Reaction of AgNO₃ with the potassium salt of the N-thiophosphorylated thiourea NH₂C(S)NHP(S)(OiPr)₂ gave a new supramolecular Ag^I complex, [AgZ]_n (Z = {NC–NP(S)(OiPr)₂}⁻) that contains both tri- and tetracoordinated Ag^I. The novel polynuclear Ag^I complex [AgZ]_n described and structurally characterized by single crystal X-ray diffraction has no precedent.