Design and construction of coordination polymers based on 2,2′-dinitro-4, 4′-biphenyldicarboxylate and imidazole-based ligands: The effect of ligand length and metal ions

Five coordination polymers, Mn-4(nbpdc)(4)(bip)(H2O)(2) (1), Co-5(nbpdc)(4)(bip)(2)(H2O)(6)(OH)(2) (2), Cu-5(nbpdc)(4)(bip)(2)(H2O)(2)(OH)(2) (3), Zn-5(nbpdc)(4)(bip)(2)(OH)(2) (4), and Cd-2(nbpdc)(2)(bip) (5), (H(2)nbpdc = 2,2'-dinitro-4,4'-biphenyldicarboxyl acid, bip = 1,5-bis(imidazole)pentane), have been prepared and structurally characterized. In these compounds, nbpdc and bip link different secondary building units (SBUs) to construct a variety of architectures based on different metals. Compound 1 presents a 3D hex net based on infinite rod-shaped SBUs. Compound 2 shows a 3D framework with mab topology based on Co-5 clusters and exhibits an interesting self-penetration feature. Compound 3 presents a 3D framework with pcu topology constructed by Cu-5 clusters. Compound 4 is a 3D framework with pcu topology based on infinite rod-shaped SBUs. Compound 5, like compound 4, also exhibits pcu topology constructed by rod-shaped SBUs, but they both possess different structures. The magnetic properties of compounds 1 and 2 have been characterized.