Here we demonstrate that a fluorescent benzothiadiazole (BTD)-conjugated terphenyldicarboxylate (TPDC) linker (denoted as H-ostpdc) has been hybridized by a quinoxaline-2,3-(1H,4H)-dione (QD) moiety possessing lactam-lactim tautomerism, which was further integrated into a robust and porous UiO-68 type zirconium metal-organic framework (MOF UiO-68-osdm) by utilizing the mixed two dicarboxylate struts with the same ligand lengths. The resultant MOF UiO-68-osdm can work as a ratiometric luminescent sensor for visual and selective detection of alkyl amines. Furthermore, it can discriminate secondary alkylamines from other type amine species.

A porous Co(II)-MOF (1) was synthesized by the combination of a bent imidazole-bridged ligand and p-phthalic acid (PTA) with Co(OAc)2 under solvothermal conditions. This Co(II)-MOF (1) is able to undergo a reversible MeOH substitution reaction on the Co(II) center via a single-crystal-to-single-crystal process. The desolvated Co(II)-MOF (2) with the open Co(II) sites is very stable (up to 350 °C). Furthermore, 2 is a highly active heterogeneous catalyst for various organic substrates oxidation in the presence of tert-butyl hydroperoxide (TBHP) under milder conditions. The importance of open Co(II) sites in 2 for the organic substrates oxidation is directly evidenced by the single-crystal X-ray diffraction.

A stable porous Ag(I)-MOF with new topology is constructed from AgSbF6 and 3,6-bis[2-(4-oxide-quinoxaline)-yl]-4,5-diaza-3,5-octadiene (L). This compound can be a highly selective porous MOF material to effectively separate benzene from its six-membered cyclic organic analogues such as cyclohexane, cyclohexene and o-, m-, p-xylene under ambient conditions in both vapor and liquid phases.

A new Ag NP-loaded organic molecular cage, which can act as a highly efficient heterogeneous catalyst for the selective reduction of nitroarenes to azo compounds under visible light irradiation, is reported.

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The coordination chemistry of the oxadiazole-containing rigid bidentate ligands 2,5-bis-(4-pyridyl)-1,3,4-oxadiazole (L1) and 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (L2) with inorganic M(II) (M ) Zn and Cu) salts has been investigated. Two new coordination polymers (1 and 2) and two new bimetallic macrocyclic supramolecular complexes (3 and 4) were synthesized from solution reactions of L1 and L2 with inorganic M(II) (M ) Zn and Cu) salts, respectively. 16) Å, c ) 9.6449(6) Å, β ) 99.9920(10)°, Z ) 2) was obtained by combination of L1 with Zn(ClO 4 )‚6H 2 O in a CH 2 Cl 2 /CH 3 CN mixed-solvent system. The structure features one-dimensional chains that are cross-linked to each other by weak noncovalent π-π interactions (alternating face-to-face stacking of coordinated and uncoordinated L1 molecules) to generate a novel two-dimensional network. 5) Å, β ) 101.4270(10)°, Z ) 4) was obtained by combination of L1 with Zn(NO 3 ) 2 ‚6H 2 O in the same solvent system. It forms with an unique H-bonded three-dimensional framework that contains rhombic channels (crystallographic dimensions, 18 × 10 Å 2 ) running down the crystallographic c axis. Inside the channels are double columns of CH 3 CN molecules, stacked neatly upon one another. [Zn(L2)(H 2 O) 3 (NO 3 )] 2 (NO 3 ) 2 (3; monoclinic, P2 1 /c, a ) 13.8786(7) Å, b ) 12.5179(7) Å, c ) 9.8966(5) Å, β ) 97.5790(10)°, Z ) 2) and {[Cu(L2)(CH 3 CN)(NO 3 )] 2 (4; triclinic, P h 1, a ) 7.7416(5) Å, b ) 8.5956(5) Å, c ) 13.3020(8) Å, R ) 74.3470(10)°, β ) 78.4420(10)°, γ ) 86.2340(10)°, Z ) 1) were generated from the reactions of L2 with Zn(NO 3 ) 2 ‚6H 2 O and Cu(NO 3 ) 2 ‚6H 2 O in a CH 2 Cl 2 /CH 3 CN mixed-solvent system, respectively. Both 3 and 4 adopt a novel bimetallic macrocyclic structural motif, consisting of M 2 (L2) 2 (M ) Zn and Cu) ringlike units. Hydrogen-bonding interactions in 3 and noncovalent π-π interactions in 4 play a significant role in aligning the molecular dimeric squares in the solid state. Compounds 3 and 4 are soluble in both water and organic solvents. In addition, both compounds are luminescent in the solid state and a large red shift in the emission is observed between the free ligand L2 and the ligand incorporated into both complexes 3 and 4.

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Four MII (M=ZnII, CdII, HgII) coordination polymers were designed and synthesized based on two pyridine N‐oxide bridging ligands: 3,5‐bis(4‐pyridyl)pyridine N‐oxide and 2,6‐bis(3‐pyridyl)pyridine N‐oxide. The resulting polymers all feature a one‐dimensional chain motif and contain free pyridyl moieties. More importantly, they exhibit interesting ligand‐centered (pyridyl N‐oxide) catalytic behavior, and can be used as highly heterogeneous catalysts to promote the Knoevenagel condensation reaction under ambient conditions.