Ancillary Ligands Dependent Structural Diversity of A Series of Metal–Organic Frameworks Based on 3,5-Bis(3-carboxyphenyl)pyridine
dataset
posted on 2013-06-05, 00:00 authored by Liming Fan, Xiutang Zhang, Zhong Sun, Wei Zhang, Yuanshuai Ding, Weiliu Fan, Liming Sun, Xian Zhao, Han LeiA series of novel multidimensional
transition metal–organic
frameworks (MOFs), [Cu(Hbcpb)2]n (1), [Co(bcpb)]n (2), [Co(Hbcpb)2(1,4-bib)]n (3), {[M(bcpb)(1,4-bimb)]·xH2O}n (M = Co (4), Cu (5),
Ni (6), x = 1 for 5, 2
for 4 and 6), [Co(bcpb)(4,4′-bibp)]n (7), {[Co(bcpb)(4,4′-bibp)]·2H2O}n (8), and [Ni2(bcpb)2(4,4′-bimbp)2]n (9), were synthesized under hydrothermal
conditions in the presence of N-donor ancillary ligands [H2bcpb = 3,5-bis(3-carboxyphenyl)pyridine, 1,4-bib = 1,4-bis(1H-imidazol-4-yl)benzene,
1,4-bimb = 1,4-bis(imidazol-1-ylmethyl)benzene, 4,4′-bibp =
4,4′-bis(imidazol-1-yl)biphenyl, 4,4′-bimbp = 4,4′-bis(imidazol-1-ylmethyl)biphenyl].
Their structures have been determined by single-crystal X-ray diffraction
analyses and further characterized by elemental analyses, IR spectra,
powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses.
By adjusting the reaction pH, the H2bcpb ligand is partially
deprotonated to give the Hbcpb– form in 1 and 3, and completely deprotonated to afford the bcpb2– form in 2 and 4–9. Complex 1 exhibits a two-dimensional (2D)
(3,6)-connected kgd topology with the Schläfli symbol of (43)2(46·66·83). The three-dimensional (3D) framework of 2 is
defined as a (4,4)-connected pts topology with the Schläfli
symbol of (42·84). Complex 3 displays a (4,6)-connected pcu topology with the Schläfli
symbol of (412·63) built from 44 2D nets with the help of 1,4-bib. Complexes 4–6 are isomorphism and show a 3D (3,5)-connected mbm framework
with the Point Schläfli symbol of (4·62)(4·66·83). The supramolecular isomers of 7 and 8, resulted from the different pH in the
reaction, exhibit (3,5)-connected (42·67·8)(42·6) 3,5-L2 and (4,6)-connected (44·610·8)(44·62) fsc topology, respectively. Complex 9 can be regard
as an unprecedented (3,5)-connected 3D 3,5-T1 frameworks with the
point Schläfli symbol of (42·65·83)(42·6). The results revealed that the crystal
architectures and the coordination modes of H2bcpb are
attributed to the factors, including metal cations, pH, and the N-donor
ancillary ligands.
