Syntheses, Structures, and Properties of a Series of Multidimensional Metal–Organic Polymers Based on 3,3′,5,5′-Biphenyltetracarboxylic Acid and N‑Donor Ancillary Ligands
Hydrothermal reactions of aromatic 3,3′,5,5′-biphenyltetracarboxylic
acid (H<sub>4</sub>bpt) and the transitional metal cations in the
presence of rigid or flexible N-donor ancillary ligands afford nine
novel coordination polymers, namely, [M(H<sub>2</sub>bpt)(Hpptp)]<sub><i>n</i></sub> (M = Mn (<b>1</b>), Fe (<b>2</b>), Co (<b>3</b>), and Zn (<b>4</b>)), [Mn<sub>2</sub>(bpt)(Hpptp)<sub>2</sub>]<sub><i>n</i></sub> (<b>5</b>), {[Zn<sub>3</sub>(Hbpt)(bpt)(H<sub>2</sub>O)<sub>2</sub>][(4,4′-H<sub>2</sub>bmib)<sub>0.5</sub>]·H<sub>2</sub>O}<sub><i>n</i></sub> (<b>6</b>), {[Cu(bpt)<sub>0.5</sub>(4,4′-bimbp)]·H<sub>2</sub>O}<sub><i>n</i></sub> (<b>7</b>), {[Co(H<sub>2</sub>bpt)(2,7-dfo)]·H<sub>2</sub>O}<sub><i>n</i></sub> (<b>8</b>), and {[Ni<sub>2</sub>(bpt)(4,4′-bibp)<sub>2.5</sub>(H<sub>2</sub>O)]·3(H<sub>2</sub>O)}<sub><i>n</i></sub> (<b>9</b>) (Hpptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1<i>H</i>-1,2,4-triazol-5-yl)pyridine; 4,4′-bmib = 4,4′-bis(2-methylimidazol-1-yl)benzene;
4,4′-bimbp = 4,4′-bis(imidazol-1-ylmethyl)biphenyl;
2,7-dfo = 2,7-di(imidazo-1-ly)-9<i>H</i>-fluoren-9-one;
4,4′-bibp = 4,4′-bis(imidazol)biphenyl). Their structures
have been determined by single-crystal X-ray diffraction analyses,
elemental analyses, IR spectra, powder X-ray diffraction (PXRD), and
thermogravimetric (TG) analyses. Complexes <b>1</b>–<b>4</b> are isomorphism and feature a similar 2-fold interpenetrating
2D helical double layer, which is further extended via the interlayer
π···π interactions into a 3D supramolecular
structure. Complex <b>5</b> displays a pillared-layer 3D porous
network with a (6<sup>2</sup>.8)<sub>2</sub>(6<sup>2</sup>.8<sup>2</sup>.10<sup>2</sup>) topology. Compound <b>6</b> shows an unprecedented
3D host-framework consisting of Zn<sub>6</sub> clusters and exhibits
a novel 3D (5,5,5,6,9)-connected topological net with the Schläfli
symbol of (4<sup>10</sup>.6<sup>5</sup>)(4<sup>19</sup>.6<sup>16</sup>.8)(4<sup>6</sup>.6<sup>4</sup>)(4<sup>7</sup>.6<sup>3</sup>)<sub>2</sub>. The topology of <b>7</b> is an unprecedented binodal
(4,4)-connected 3D network with the Schläfli symbol of (6<sup>2</sup>.8<sup>4</sup>)(4<sup>2</sup>.8<sup>2</sup>)<sub>2</sub>.
Complex <b>8</b> exhibits a 3D (6<sup>6</sup>) structure with
left- and right-handed helical chains arranged alternately. Complex <b>9</b> is a novel trinodal (4,4,5)-connected 3D framework with
the Schläfli symbol of (6<sup>4</sup>.8<sup>2</sup>)(6<sup>5</sup>.8)(6<sup>8</sup>.8<sup>2</sup>). To the best of our knowledge,
the 3D frameworks with (5,5,5,6,9)-connected net for <b>6</b>, binodal (4,4)-connected for <b>7</b>, and trinodal (4,4,5)-connected
for <b>9</b> have never been documented to date. Moreover, the
luminescent properties of <b>4</b> and <b>6</b> have been
investigated
