A 3-D metal-organic framework of CuII perchlorate and 2-(2-pyridyl)-5-(4-pyridyl)-1,3,4-oxadiazole showing the exclusive anion-exchange selectivity to benzoate

Assembly of cu(ClO4)(2)center dot 6H(2)O and 2-(2-pyridyl)-5-(4-pyridyl)-1,3,4-oxadiazole (L) yields a 3-D MOF {[CuL2] (ClO4)(2)(H2O)(1/2)}(n) (1). Single crystal X-ray diffraction indicates that 1 has a cationic open coordination framework with lvt topology, where each Cu-II ion is connected to four L ligands in (eta(3),mu(2)) binding mode. The lattice water and perchlorate are accommodated in the 3-D host microporous framework with two types of 1-D channels along different directions. The unusual anion-exchange property is observed for 1, showing the exclusive anion-exchange selectivity with respect to benzoate in an irreversible way. (C) 2011 Elsevier B.V. All rights reserved.