| The design and synthesis of metal-organic frameworks based on the selection of ligands and metal ions has become a very attractive research field. The motive comes not only from their intriguing structural topologies, but also from the demand for applications of functional materials in the field of catalysis, gas adsorption, magnetism, luminescence, conductivity, sensing, nonlinear optics and chirality. The self-assembly of supramolecules and coordination polymers is influenced by many factors, such as the coordinative function of the ligands, the type of metal ions, the presence of solvent molecules, organic guest molecules, counter ion, the metal-to-ligand molar ratio, reaction temperature and pH value of the solution. Although a large number of polycarboxylate-based coordination polymers have been synthesized, systematic investigation of external physical or chemical stimuli effects on the structures of polycarboxylate-based coordination polymers remains rare. Therefore, systematic studies have been carried out in this paper by reaction of transition metal, dicarboxylates and a series of N-donor ligands to investigate the influence of the above conditions on the properties and construction of coordination frameworks.Twenty-three coordination polymers have been synthesized on the basis of hydrothermal technique or water solution synthesis methods and characterized by IR spectra, elemental analysis, X-ray single crystal analysis, thermal analysis, XRPD analysis, fluorescence spectroscopy and magnetic susceptibility measurement.Five new Mn(Ⅱ) metal-organic coordination polymers, [Mn(tbip)(bipy)]n (1), {[Mn(tbip)(dpe)]·1.5H2O}n (2), [Mn(tbip)(bpa)]n (3), [Mn(map)(bpa)]n (4) and {[Mn3(mip)2 (Hmip)2(bpp)2(H2O)2]·2H2O}n (5), were prepared through hydrothermal reactions of Mn(Ⅱ) acetate with H2tbip or H2mip in the presence of different dipyridyl co-ligands. More relevant to our purpose, the different structures demonstrate the influence of a second ligand on the assembly of MOFs. The thermal stability and magnetic properties of 1-5 were also studied.Eight new d10 metal-organic coordination polymers, [Zn(mip)(bpa)]n (6), [Zn(mip)(bpp)]n (7), [Cd(mip)(bpp)]n (8), [Zn2(tbip)2(bpa)(H2O)]n (9), [Zn2(tbip)2(dpe)(H2O)]n (10), {[Zn(tbip)(bpp)]·H2O}n (11), {[Cd(tbip)(bpp)(H2O)]·3H2O}n (12) and {[Cd(tbip)(H2O) (bipy)0.5]·H2O}n (13) were prepared through hydrothermal reactions of H2mip or H2tbip with different pyridyl-containing ligands. Variations in the molecular self-assembly are influenced by the substituted group in the bridging ligands. Coordination polymers 6-13 exhibit intense fluorescence emissions and may be candidates for fluorescent materials.Four new coordination polymers, [Ni(isop)(bps)(H2O)]2n·5H2O (14), [Ni(O2N-BDC) (bps)(H2O)]2n (15), [Ni(OH-BDC)(bps)2(H2O)]n (16) and {[Ni2(H2O)(tbip)2(bps)2]}n (17) have been isolated from parallel hydrothermal reactions of Ni(OAc)2·4H2O and bps with isop, O2N-BDC, OH-BDC and H2tbip, respectively. As compared to isop, the coexistence of electron-donating (-OH, -C(CH3)3) or electron-withdrawing groups (-NO2) groups in the dicarboxylate derivatives has a significant effect on the molecular self-assembly. The magnetic properties of 17 were also studied.Two novel 3D metal-organic frameworks with cobalt(Ⅱ) clusters as nodes and mixed bridging ligands as linkers, {[Co3(OH)(tbip)2(Htbip)(dps)(dpds)0.5]}n (18) and {[Co2(H2O)(tbip)2(dps)]·CH3OH·2H2O}2n (19) were obtained from the same reaction mixture but tuned by different hydrothermal temperatures, at 120℃, product 18 is a 3D MOF based on the novel triangular trinuclear cluster node, whereas at 160℃, product 19 is a 3D MOF constructed from both a linear trinuclear cluster node and a mononuclear CoⅡnode. The starting dpds reagent was partly converted into dps ligand in 18 and wholly transferred into dps in 19 via new in situ cleavage of both S-S and S-C bonds and temperature-dependent in situ ligand rearrangement of dpds. The thermal stability of 19 and magnetic properties of 18 were also studied.Reaction of H3L1 with Mn(ClO4)2·6H2O at different pH values gave two dinuclear complexes: [Mn2(HL1)2(phen)4]·8H2O (20) and [Mn2L1(phen)4(H2O)]ClO4·3H2O (21). Additionally, two copper(Ⅱ) complexes, [K2Cu(L2)2(H2O)2]N (22) and [CuL2(H2O)]2·2H2O (23), were prepared by a one-pot reaction of l,3-phenylenebis(sulfonyl chloride), glycine, and KOH or triethylamine in the presence of CuⅡions. An Unprecedented self-assembled (H2O)30 cluster containing a puckered (H2O)12 ring core was found in 20. Magnetic properties of 20-23 were also measured.
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