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The urothermal reactions of Co(II)/Zn(II) salts with the diverse carboxylic acid and 1,3,5,-tris(1-imidazolyl)benzene(tib) ligands afforded three novel MOFs, namely, [Co3(tib)2(abdc)2(ox)]2·6H2O (1), [Co3O(tib)(abdc)2(DMI)]·2DMI·2H2O (2) and [Zn3I2(tib)2(napdc)2]·2DMI·2H2O (3), (H2abdc = 5-amino-1,3-benzenedicarboxylate, H2napdc = 1,4-naphthalene dicarboxylic acid and DMI = 1,3-dimethyl-2-imidazolidinone). In compounds 1 and 2, the Co(II) atoms are connected by polycarboxylate ligands to form two-dimensional (2D) layers that are pillared by tib ligands leading to the formation of 3D porous frameworks. In compound 3, the Zn(II) atoms are linked by tib ligands to form one-dimensional ribbon-like chains which are further connected by polycarboxylate ligands, making a 3D framework possible. Compound 1 can selectively adsorb unsaturated hydrocarbon molecules (C2H2 and C2H4) and saturated hydrocarbon molecules (C2H6 and CH4). Specifically, compound 1 has high IAST selectivity for acetylene and methane (0.50 : 0.50, v/v) at 273 K and 1 bar. DFT calculations reveal that the π-conjugated hexagonal carbon ring may be the primary adsorption site because there are π–π interactions between the unsaturated hydrocarbon molecules (C2H2 and C2H4) and the π-conjugated hexagonal carbon ring in the framework of compound 1. [ABSTRACT FROM AUTHOR]

The urothermal reactions of Co(II)/Zn(II) salts with the diverse carboxylic acid and 1,3,5,-tris(1-imidazolyl)benzene(tib) ligands afforded three novel MOFs, namely, [Co3(tib)2(abdc)2(ox)]2·6H2O (1), [Co3O(tib)(abdc)2(DMI)]·2DMI·2H2O (2) and [Zn3I2(tib)2(napdc)2]·2DMI·2H2O (3), (H2abdc = 5-amino-1,3-benzenedicarboxylate, H2napdc = 1,4-naphthalene dicarboxylic acid and DMI = 1,3-dimethyl-2-imidazolidinone). In compounds 1 and 2, the Co(II) atoms are connected by polycarboxylate ligands to form two-dimensional (2D) layers that are pillared by tib ligands leading to the formation of 3D porous frameworks. In compound 3, the Zn(II) atoms are linked by tib ligands to form one-dimensional ribbon-like chains which are further connected by polycarboxylate ligands, making a 3D framework possible. Compound 1 can selectively adsorb unsaturated hydrocarbon molecules (C2H2 and C2H4) and saturated hydrocarbon molecules (C2H6 and CH4). Specifically, compound 1 has high IAST selectivity for acetylene and methane (0.50 : 0.50, v/v) at 273 K and 1 bar. DFT calculations reveal that the π-conjugated hexagonal carbon ring may be the primary adsorption site because there are π–π interactions between the unsaturated hydrocarbon molecules (C2H2 and C2H4) and the π-conjugated hexagonal carbon ring in the framework of compound 1. [ABSTRACT FROM AUTHOR]

Five novel hybrid compounds, [Mo8O26Cu2(4-abpt)2]n·4nH2O (1), (4-H2abpt)2[Mo8O26] (2), [Mo8O26Cu2(3-abpt)2(H2O)2]n(3), [MoO4Cu(3-abpt)(H2O)]n(4), and [Mo6O19Co(3-abpt)2]n·4nH2O (5) were prepared by reacting MoO3/(NH4)6Mo7O24with 4-amino-3,5-bis(3/4-pyridyl)-1,2,4-triazole (3/4-abpt) and corresponding metal salts. Compound 1is a 2D coordination polymer containing extended γ-[Mo8O26]4−and [Cu2(4-abpt)2]4+ribbons. Compound 2is a supramolecular hybrid aggregate composed of H-bond linking β-[Mo8O26]4−and 4-H2abpt2+. Compound 3exhibits a 2D rectangular network constructed by isolated β-[Mo8O26]4−clusters and [Cu2(3-abpt)2]4+. In compound 4, each MoO42−anion links two Cu(ii) ions to form a S-type [CuMoO4]nchain, which is further linked by bidentate 3-abpt to form a 2D wave-like network. In complex 5, unprecedented cyclic [Mo6O19]2−cluster links two neighbouring hexamolybdates and two Co(ii) ions to form a 2D [CoMo6O19]nnetwork, which is further pillared by tetradentate 3-abpt to generate a 3D metal–organic framework. These compounds are thermally stable under 250 °C. The composites of the final residues were analyzed by PXRD. [ABSTRACT FROM AUTHOR]