Solvent/Temperature and Dipyridyl Ligands Induced Diverse Coordination Polymers Based on 3-(2′,5′-Dicarboxylphenyl)pyridine

Eleven new multidimensional transition coordination polymers, [Cd-2(dcpy)(2)(H2O)] (1), [Cd(dcpy)]center dot H2O (2), [Cd(dcpy)(H2O)(1.5)]center dot 2H(2)O (3), [Cd(dcpy)(bipy)(0.5)(H2O)]center dot 5H(2)O (4), [Cd-2(dcpy)(2)(bipy)(H2O)(3)]center dot 2.5H(2)O (5), [Cd-2(dcpy)(2)(bipy)]center dot 4H(2)O (6), [Cd(dcpy)(bpa)(0.5)]center dot 2H(2)O (7), [Ni(dcpy)(H2O)(2)] (8), [Ni(dcpy)(bpe)(0.5)(H2O)]center dot 3H(2)O (9), (Ni(dcpy)(bpe)(0.5)(H2O)]center dot 0.5H(2)O (10), and [Ni(dcpy)(bpa)(0.5)(H2O)(2)]center dot H2O (11), have been synthesized by using a tritopic ligand 3-(2',5'-dicarboxylphenyl)pyridine acid (H(2)dcpy) and three different N-donor ancillary ligands (bipy = 4,4'-bipyridine, bpe = 1,2-bi(4-pyridyl)ethene, and bpa = 1,2-bi(4-pyridyl)ethane) in different solvents and temperatures. 1 is a four-connected three-dimensional (3D) framework based on two kinds of Cd-O-Cd and Cd-(COO)-Cd chains. 2 shows also a four-connected 3D framework with one-dimensional (1D) channels formed by double left- and right-handed helical chains. 3 displays a 3D microporous framework composed of Cd2O3 as a secondary building unit (SBU) with a (4,6)-connected net. 4 is a two-dimensional (2D) layer based on Cd2O2 SBU and further stacks to generate a 3D supramolecular framework with open channels. 5 is a rare 3D homochiral microporous framework with left-handed helical chains. 6 presents the first (3,4,6)-connected 3D self-penetrating framework based on 1D metal organic nanotubes (MONTs). 7 is a (3,4)-connected 3D microporous pillar-layer framework with ID square channels filled by left- or right-handed helical water clusters chains. 8 is a 2D (3,6)-connected net based on Ni-2 dimers. 9 shows a wavelike 2D stacked layer framework possessing two types of open channels. 10 is a structural isomer of 9, showing an intriguing (3,4)-connected self-penetrating network, while 11 exhibits a 2D (3,4)-connected layer. The effects of solvents, temperatures, metal cations, and the lengths and rigidness/flexibility of the dipyridyl ligand on the crystal architectures are discussed. The solid-state photoluminescence for 1-7 and the magnetic properties for 8 were also investigated. Gas adsorption studies for 9 shows a high selective adsorption of CO2 over N-2.