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 (H4bpt) and the transitional metal cations in the
presence of rigid or flexible N-donor ancillary ligands afford nine
novel coordination polymers, namely, [M(H2bpt)(Hpptp)]n (M = Mn (1), Fe (2), Co (3), and Zn (4)), [Mn2(bpt)(Hpptp)2]n (5), {[Zn3(Hbpt)(bpt)(H2O)2][(4,4′-H2bmib)0.5]·H2O}n (6), {[Cu(bpt)0.5(4,4′-bimbp)]·H2O}n (7), {[Co(H2bpt)(2,7-dfo)]·H2O}n (8), and {[Ni2(bpt)(4,4′-bibp)2.5(H2O)]·3(H2O)}n (9) (Hpptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-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)-9H-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 1–4 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 5 displays a pillared-layer 3D porous
network with a (62.8)2(62.82.102) topology. Compound 6 shows an unprecedented
3D host-framework consisting of Zn6 clusters and exhibits
a novel 3D (5,5,5,6,9)-connected topological net with the Schläfli
symbol of (410.65)(419.616.8)(46.64)(47.63)2. The topology of 7 is an unprecedented binodal
(4,4)-connected 3D network with the Schläfli symbol of (62.84)(42.82)2.
Complex 8 exhibits a 3D (66) structure with
left- and right-handed helical chains arranged alternately. Complex 9 is a novel trinodal (4,4,5)-connected 3D framework with
the Schläfli symbol of (64.82)(65.8)(68.82). To the best of our knowledge,
the 3D frameworks with (5,5,5,6,9)-connected net for 6, binodal (4,4)-connected for 7, and trinodal (4,4,5)-connected
for 9 have never been documented to date. Moreover, the
luminescent properties of 4 and 6 have been
investigated
