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 4 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 2 bpt)(Hpptp)] n (M = Mn ( 1 ), Fe ( 2 ), Co ( 3 ), and Zn ( 4 )), [Mn 2 (bpt)(Hpptp) 2 ] n ( 5 ), {[Zn 3 (Hbpt)(bpt)(H 2 O) 2 ][(4,4′-H 2 bmib) 0.5 ]·H 2 O} n ( 6 ), {[Cu(bpt) 0.5 (4,4′-bimbp)]·H 2 O} n ( 7 ), {[Co(H 2 bpt)(2,7-dfo)]·H 2 O} n ( 8 ), and {[Ni 2 (bpt)(4,4′-bibp) 2.5 (H 2 O)]·3(H 2 O)} n ( 9 ) (Hpptp = 2-(3-(4-(pyridin-4-yl)phenyl)-1 H -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 H -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 (6 2 .8) 2 (6 2 .8 2 .10 2 ) topology. Compound 6 shows an unprecedented 3D host-framework consisting of Zn 6 clusters and exhibits a novel 3D (5,5,5,6,9)-connected topological net with the Schläfli symbol of (4 10 .6 5 )(4 19 .6 16 .8)(4 6 .6 4 )(4 7 .6 3 ) 2 . The topology of 7 is an unprecedented binodal (4,4)-connected 3D network with the Schläfli symbol of (6 2 .8 4 )(4 2 .8 2 ) 2 . Complex 8 exhibits a 3D (6 6 ) 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 (6 4 .8 2 )(6 5 .8)(6 8 .8 2 ). 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.