CuII Coordination Polymers Capable of Gelation and Selective SO4–2 Separation

A crystal engineering rationale has been exploited to generate a series of CuII coordination polymers namely [{Cu(μ-L1)(SO4)(H2O)3}·H2O]∝CP1, [{Cu(μ-L1)2(H2O)2}F·2H2O]∝CP2 [{Cu(μ-L1)2(H2O)2}Cl·H2O]∝CP3 and [{Cu(μ-L1)2(H2O)2}Br·H2O]∝CP4 derived from N, Ń-(3-pyridyl) m-phenyleneurea (L1) capable of gelling aqueous solvents (DMF/water); in situ crystallization of CP1 has been exploited to separate SO42- anion selectively from a complex mixture of oxo anions (SO42–, NO3–, ClO4–, CF3SO3–). While the gels are characterized by optical-, scanning electron microscopy and rheology, structure–property (gelation, as well as anion separation) correlation has been attempted by using single crystal- and powder-X-ray diffraction data.