From 1D Coordination Polymers to Metal Organic Frameworks by the Use of 2-Pyridyl Oximes

The synthesis and characterization of coordination polymers and metal-organic frameworks (MOFs) has attracted a significant interest over the last decades due to their fascinating physical properties, as well as their use in a wide range of technological, environmental, and biomedical applications. The initial use of 2-pyridyl oximic ligands such as pyridine-2 amidoxime (H(2)pyaox) and 2-methyl pyridyl ketoxime (Hmpko) in combination with 1,2,4,5-benzene tetracarboxylic acid (pyromellitic acid), H(4)pma, provided access to nine new compounds whose structures and properties are discussed in detail. Among them, [Zn-2(pma)(H(2)pyaox)(2)(H2O)(2)](n)(3) and [Cu-4(OH)(2)(pma)(mpko)(2)](n)(9) are the first MOFs based on a 2-pyridyl oxime with9possessing a novel 3,4,5,8-c net topology. [Zn-2(pma)(H(2)pyaox)(2)](n)(2), [Cu-2(pma)(H(2)pyaox)(2)(DMF)(2)](n)(6), and [Cu-2(pma)(Hmpko)(2)(DMF)(2)](n)(8) join a small family of coordination polymers containing an oximic ligand.9exhibits selectivity for Fe(III)ions adsorption, as was demonstrated by a variety of techniques including UV-vis, EDX, and magnetism. DC magnetic susceptibility studies in9revealed the presence of strong antiferromagnetic interactions between the metal centers, which lead to a diamagnetic ground state; it was also found that the magnetic properties of9are affected by the amount of the encapsulated Fe(3+)ions, which is a very desirable property for the development of magnetism-based sensors.