Two kinds of calixarene-based metal–organic coordination cages were obtained at different pH values despite using the same bridging ligand, either 5-(pyridin-3-yl)isophthalic acid (L1) or 5-(5-fluoropyridin-3-yl)isophthalic acid (L2), namely, [Co4(TC4A)Cl]4(Ln)4(HCOO)4(H2O)4]}·26DMF (CIAC-117 and CIAC-119) and H4[Co4(TC4A)Cl]4(Ln)8}·18CH3OH·33DMA (CIAC-118 and CIAC-120), where TC4A represents deprotonated p-tert-butylthiacalix[4]arene, and DMF and DMA represent N,N-dimethylformamide and N,N-dimethylacetamide, respectively. Tetrahedral coordination cages (CIAC-117 and CIAC-119) with shuttlecock-like Co4-TC4A secondary building units (SBUs) as the vertices and L1 and L2 as the three-connected linkers were prepared in the presence of tetramethylammonium hydroxide, while truncated octahedral coordination cages (CIAC-118 and CIAC-120) with L1 and L2 as the two-connected linkers were generated upon the addition of HCl. For CIAC-117, two types of activation methods, solvent exchange-heating and direct heating, were used to investigate the removal of guest molecules in the structure. N2 adsorption properties of activated samples were studied. Moreover, selective dye sorption of CIAC-120 was investigated.
A new approach in which a low symmetry cluster meets a low symmetry ligand to sharply boost the thermal stability of a MOF via additional inter-linker interactions is presented for the first time, leading to the successful synthesis of a novel binuclear Co-based MOF, [Co2(L1)2DMF]·1.5DMF·0.75MeOH·1.5H2O}∞ (H2L1 = 5-(pyridin-3-yl) isophthalic acid, NJU-Bai62: NJU-Bai for Nanjing University Bai group)
A Distorted [Mn<sub>2</sub>(COO)<sub>4</sub>N<sub>2</sub>] Cluster Based Metal–Organic Framework with (3,3,6) Topology and Selective Adsorption of CO<sub>2</sub>
作者:Jingjing Jiang、Qian Wang、Mingxing Zhang、Junfeng Bai
DOI:10.1021/acs.cgd.7b00206
日期:2017.4.5
5-(pyridin-3-yl)isophthalic acid (H2L), a new distorted [Mn2(COO)4N2] cluster based metal–organicframework with (3,3,6) topology, [Mn2(L)2DMF]·DMF·MeOH (NJU-Bai33; DMF = N,N- dimethylformamide), was synthesized, which exhibits a new point (Schläfli) symbol of (4·62)2(42·68·85), contains open metal sites, and shows selectiveadsorption of CO2 over N2 and CH4 with CO2 uptake amounts high up to 7.9 and 4.2 wt %
Nanotubular Metal−Organic Frameworks with High Porosity Based on T-Shaped Pyridyl Dicarboxylate Ligands
作者:Shenglin Xiang、Jing Huang、Lei Li、Jianyong Zhang、Long Jiang、Xiaojun Kuang、Cheng-Yong Su
DOI:10.1021/ic102188v
日期:2011.3.7
Two nanotubular metal organic frameworks (MOFs), Cu(L1)center dot 2H(2)O center dot 1.5DMF}(infinity) (1) and Cu-2(L-2)(2)(H2O)(2)center dot 7H(2)O center dot 3DMF}(infinity) (2), with novel topologies have been constructed based on Cu2+, 5-(pyridin-4-yl)isophthalic acid (L1) and 5-(pyridin-3-yl)isophthalic acid (L2), respectively. Two MOFs were characterized by IR spectroscopy, thermogravimetry single-crystal, and powder X-ray diffraction methods. Network analysis reveals a two-nodal (3,6)connected (4.6(2))(2)(4(2).6(10).8(3)) net and a three-nodal (3,4)-connected (4.8(2))(4)(4(2).8(2).10(2))(2)(8(4).12(2)) net. Interpenetration is inherently prevented by both of the topologies of the frameworks. The porosity of MOF 1 was confirmed by N2 and CO2 gas adsorption investigations. MOF 1 exhibits remarkable hydrogen sorption hysteresis at low pressure and a H-2 uptake capacity of 1.05 wt % at 77 K and 1 atm.