Active Sites Decorated Nonpolar Pore-Based MOF for One-step Acquisition of C2 H4 and Recovery of C3 H6.

Herein, a 2-fold interpenetrated metal-organic framework (MOF) Zn-BPZ-TATB with accessible N/O active sites in nonpolar pore surfaces was reported for one-step C2 H4 purification from C2 H6 or C3 H6 mixtures as well as recovery of C3 H6 from C2 H6 /C3 H6 /C2 H4 mixtures. The MOF exhibits the favorable C2 H6 and C3 H6 uptakes (>100 cm3 g-1 at 298 K under 100 kPa) as well as selective adsorption of C2 H6 and C3 H6 over C2 H4 . The C3 H6 - and C2 H6 -selective feature were investigated detailedly by experimental tests as well as sorption kinetic studyies. Molecular modelling revealed the multiple interactions between C3 H6 or C2 H6 molecules and methyl groups as well as triazine rings in pores. Zn-BPZ-TATB not only can directly generate 323.4 L kg-1 and 15.4 L kg-1 of high-purity (≥99.9 %) C2 H4 from C3 H6 /C2 H4 and C2 H6 /C2 H4 mixtures, but also provide a large high-purity (≥99.5 %) C3 H6 recovery capacity of 60.1 L kg-1 from C3 H6 /C2 H4 mixtures. More importantly, the high-purity C3 H6 (≥99.5 %) and C2 H4 (≥99.9 %) with the productivities of 38.2 and 12.7 L kg-1 can be simultaneously obtained from C2 H6 /C3 H6 /C2 H4 mixtures through a single adsorption/desorption cycle.

One Co-MOF with F Active Sites for Separation of C2H2 from CO2, C2H4, and CH4.

Separating acetylene (C2H2) from other light hydrocarbons and carbon dioxide (CO2) mixtures under mild conditions poses significant challenges due to the remarkably similar properties between C2H2 and those gases. For the goal of C2H2 separation, a F-functionalized organic linker, H2F-PyIP = 2-fluorine-5-(4-pyridyl)isophthalic acid, was designed, and the corresponding metal-organic framework (MOF), {[Co2(F-PyIP)2DMF]·4H2O}n (1), was constructed. The MOF with open channels decorated by the active sites of the F groups revealed the exceptional C2H2 uptake and selectivity over CO2, C2H4, and CH4. The breakthrough experiments with different molar ratios of C2H2-C2H4, C2H2-CO2, and other gas mixtures further verified superior separation capacity of the MOF. In particular, the dynamic separation time intervals for gas mixtures (C2H2/CO2 = 1:1, 1:5, 1:10, and 1:20) fell in the range 30-44 min, highlighting the potential of the MOF for tackling the challenging C2H2/CO2 separation process.

Cu-MOFs with Rich Open Metal and F Sites for Separation of C2H2 from CO2 and CH4.

Herein, we used the 4-fluoro-[1,1'-biphenyl]-3,4',5-tricarboxylic acid (H3fbptc) ligand to design and construct a new metal-organic framework (MOF), [Cu3(fbptc)2(H2O)3]·3NMP (1), which possesses rich accessible metal sites and F functional groups in the porous walls and shows high uptake for C2H2 (119.3 cm3 g-1) and significant adsorption selectivity for C2H2 over CH4 (14.4) and CO2 (3.6) at 298 K and 100 kPa. In particular, for the gas mixtures of C2H2-CH4 and C2H2-CO2, the MOF reveals large breakthrough time ratios (C2H2/CH4 = 13, C2H2/CO2 = 5.9), which are particularly prominent in dynamic breakthrough experiments, also confirming the excellent potential for the practical separation of C2H2 from two-component mixtures (C2H2-CH4 and C2H2-CO2) and even three-component mixtures (C2H2-CO2-CH4).

Boosting Ethane/Ethylene Separation by MOFs through the Amino-Functionalization of Pores.

Adsorption technology based on ethane-selective materials is a promising alternative to energy-intensive cryogenic distillation for separating ethane (C2 H6 ) and ethylene (C2 H4 ). We employed a pore engineering strategy to tune the pore environment of a metal-organic framework (MOF) through organic functional groups and boosted the C2 H6 /C2 H4 separation of the MOF. Introduction of amino (-NH2 ) groups into Tb-MOF-76 not only decreased pore sizes but also facilitated multiple guest-host interactions in confined pores. The NH2 -functionalized Tb-MOF-76(NH2 ) has increased C2 H6 and C2 H4 uptakes and C2 H6 /C2 H4 selectivity. The results of experimental and simulated transient breakthroughs reveal that Tb-MOF-76(NH2 ) has significantly improved one-step separation performance for C2 H6 /C2 H4 mixtures with a high C2 H4 (>99.95 %) productivity of 17.66 L kg-1 compared to 7.53 L kg-1 by Tb-MOF-76, resulting from the suitable pore confinement and accessible -NH2 groups on pore surfaces.

TXNIP knockout improves cardiac function after myocardial infarction by promoting angiogenesis and reducing cardiomyocyte apoptosis.

Background: Myocardial infarction (MI) is a common cause of death. Thioredoxin-interacting protein (TXNIP) expression increases after MI, and it exerts a negative regulatory effect on cardiac function after MI. Our study aimed to investigate the specific regulatory mechanism of TXNIP on angiogenesis and cardiomyocyte apoptosis after MI. Methods: The TXNIP gene knock-in (TXNIP-KI) and knock-out (TXNIP-KO) mice were generated, respectively. Eight-week-old male TXNIP-KO, TXNIP-KI, and wild type (WT) mice were subjected to MI by permanent ligation of the left anterior descending artery. Cardiomyocyte apoptosis was detected by TUNEL assay on the 4th post-surgery day. The expressions of TXNIP, hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), phosphorylated protein kinase B (p-AKT), p-AMP-activated protein kinase (p-AMPK), cleaved caspase-3, and caspase-3 were detected by Western blot. Quantitative real-time PCR was performed to detect the expression of TXNIP, HIF-1α, VEGF, prolyl hydroxylase (PHD) 1, and factor inhibiting HIF (FIH). In addition, the superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in each group were also measured. On day 7 after MI, the hearts of sacrificed animals were analyzed by immunohistochemistry to assess CD31 expression and determine the density of angiogenesis. One month after treatment, the cardiac functional and structural changes were determined by echocardiography and the level of myocardial fibrosis was observed by Masson staining. Results: Compared with WT mice, TXNIP-KO mice had a significantly improved cardiac functional recovery after MI, and the proportion of myocardial fibrosis area was dramatically reduced, cardiomyocyte apoptosis was decreased, and angiogenesis was significantly increased; TXNIP-KI mice reversed in these changes. The expression of HIF-1α, p-AKT, and p-AMPK increased after MI in TXNIP-KO mice, and the mRNA expression of PHD 1 and FIH decreased. TXNIP-KI mice reversed in these changes. Conclusions: After MI, TXNIP down-regulated the level of HIF-1α and VEGF, reduced the number of angiogenesis, increased cardiomyocyte apoptosis, and ultimately led to a poor prognosis of ischemic myocardium. TXNIP was a protein with negative effects after MI and was expected to be a target for the prevention and treatment of MI.

One-Step C2 H4 Purification from Ternary C2 H6 /C2 H4 /C2 H2 Mixtures by a Robust Metal-Organic Framework with Customized Pore Environment.

One-step C2 H4 purification from ternary C2 H6 /C2 H4 /C2 H2 mixtures by a single adsorbent is of great industrial significance, but few adsorbents achieve this separation. Herein, we report a robust metal-organic framework (MOF) that possesses methyl-decorated nonpolar pores and shows one-step C2 H4 purification (purity >99.9 %) from binary C2 H6 /C2 H4 mixtures and ternary C2 H6 /C2 H4 /C2 H2 mixtures. The methyl groups in pores provide a suitable pore environment to simultaneously enhance the adsorption capacity for C2 H2 and C2 H6 compared to C2 H4 . Simulations revealed the multiple interactions between C2 H6 or C2 H2 molecules and the pore wall, while the interactions with C2 H4 molecules are weak and also unfavorable due to the repulsion from methyl groups in pores. The MOF displays high C2 H6 and C2 H2 uptakes and benchmark C2 H6 /C2 H4 selectivity (2.2), surpassing all of the reported MOFs for one-step C2 H4 purification from ternary C2 H6 /C2 H4 /C2 H2 mixtures.

A new metal-organic framework based on rare [Zn4F4] cores for efficient separation of C2H2.

Assembly via 1,4-benzenedicarboxylate linkers and Zn2+ ions afforded an MOF containing rare [Zn4F4] cubane core, showing excellent separation for C2H2-CO2 and C2H2-CH4 mixtures. Dynamic breakthrough experiments and grand canonical Monte Carlo calculations were carried out to confirm the feasibility of the MOF for the separation application of C2H2.

Efficient C2Hn Hydrocarbons and VOC Adsorption and Separation in an MOF with Lewis Basic and Acidic Decorated Active Sites.

To help address efficient separation of C2Hn light hydrocarbons and C2H2/CO2 in the chemical industry, the self-assembly via an azolate-carboxylate ligand and Co(II) ion gave rise to a new porous MOF material, [Co(btzip)(H2btzip)]·2DMF·2H2O (1) (H2btzip = 4,6-bis(triazol-1-yl)isophthalic acid). In the MOF, the pores are modified by rich uncoordinated triazolyl Lewis basic N atoms and acidic -COOH groups, which strengthen interactions with C2Hn hydrocarbons and CO2 molecules, leading to high adsorption amounts for C2H2, C2H4, C2H6, and CO2 and remarkable separation efficiency for C2Hn-CH4, CO2-CH4, and C2H2-CO2 mixtures, as confirmed by breakthrough experiments on the realistic gas mixtures. The MOF also reveals outstanding selective adsorption ability for benzene/toluene, methanol/1-propanol, methanol/2-propanol, and 2-propanol/1-propanol isomers. Molecular simulations disclose the different adsorption sites in the MOF for various adsorbates.

Nonenzymatic Glucose Sensing and Magnetic Property Based On the Composite Formed by Encapsulating Ag Nanoparticles in Cluster-Based Co-MOF.

Utilizing the oxygen-bridged 5,5'-oxidiisophthalic acid (H4L) linker, one Co(II)-based 3D porous MOF {[Co5(L)2(OH)2(OH2)2(H2O)4]·2DMF·H2O}n (1) with pentanuclear [Co5(µ3-OH)2(µ2-OH2)2]8+ cluster was prepared. The glassy carbon electrode was modified by 1, and the obtained electrode revealed electrocatalytic performance for glucose oxidation. The porous MOF matrix is beneficial for dispersing Ag nanoparticles evenly in the interior cages or channels, so Ag@1 composite composed of both Ag nanoparticles and MOF was further prepared through deposition-reduction method to enhance electrocatalytic activity. The result demonstrates that the glucose oxidation by Ag@1 was greatly increased with low detection limit (1.32 µM) and good selectivity and sensitivity (0.135 µA µM-1), which promote the application of MOF-template porous composites as advanced electrochemical sensor materials. Furthermore, 1 shows an interesting magnetic spin-glass slow dynamics for the existing of peculiar pentanuclear Co(II) clusters.

Luminescent and Magnetic Properties of Coordination Polymers Induced by Coordinating Modes of a Bis(oxamate) Ligand.

The reactions of an unexploited N,N'-5-carboxyl-1,3-phenylenebis(ethyl oxamate) (HEt2 L) ligand with different Mn2+ and Cd2+ salts under solvothermal conditions afforded four three-dimensional (3D) coordination polymers (CPs): [Mn1.5 L(H2 O)2 ]⋅H2 O (1) [Mn2 L(C2 O4 )0.5 (NMP)(H2 O)] ⋅ NMP (2), [Cd1.5 L(H2 O)2.5 ] ⋅ H2 O (3) and [Cd2 L(C2 O4 )0.5 (H2 O)3 ] ⋅ H2 O (4) (NMP=N-methyl pyrrolidone). L, generated by the in-situ hydrolysis of HEt2 L, displays four kinds of coordinating modes through oxamate and carboxylate groups as well as different syn-syn and syn-trans configurations. The resulting novel (3,4,5)-, (3,4,6)-, (4,5)- and (4,4,4,5)-connected topologies for 1-4 were formed. Among them, 1 has interesting 1D metal-oxamate zigzag chains, 2 contains 1D channels with a free void of 52.5 %, 3 consists of an unprecedented Cd-oxamate layer, 4 has a novel Cd-oxamate-oxalate chain. The antiferromagnetic interactions of 1 and 2 were observed, meanwhile 3 and 4 exhibit solid-state luminescence with the maximum emission bands at 483 and 479 nm, respectively, under an excitation of 332 nm.

A new layer-stacked porous framework showing sorption selectivity for CO2 and luminescence.

A new metal-organic framework, [Zn3(µ3-OH)(tzba)2(bpy)(H2O)]OH·DMF (1), was solvothermally synthesized by employing tetrazolate-carboxylate 4-(1H-tetrazol-5-yl) benzoic acid (H2tzba) linker and 2,2'-bipyridine (bpy) chelating coligand. 1 contains novel Zn6(µ3-OH)2(µ2-H2O)2(COO)4(N4C)2 hexanuclear clusters and reveals a three-dimensional (3D) microporous supramolecular framework based on the stacked 2D layers. The highly polar pores cause not only strong affinity towards CO2 molecules but also a significant selective adsorption of CO2 over CH4. Meanwhile, the multiple binding sites for CO2 in the framework were determined by Grand Canonical Monte Carlo (GCMC) simulations. 1 also shows strong blue luminescence from ligand-to-metal charge transfer (LMCT).

Ligand Configuration-Induced Manganese(II) Coordination Polymers: Syntheses, Crystal Structures, Sorption, and Magnetic Properties.

Three new coordination polymers, {[Mn3(pzbtz)2(Cl)2(H2O)2]·4H2O}n (1), {Mn2(pzbtz)(SO4)(H2O)3]·3H2O}n (2), and {[Mn3(pzbtz)3(H2O)3]·1.5DMA·2H2O}n (3), have been solvothermally synthesized with MnCl2/MnSO4 and a bitriazole ligand, 5'-(pyrazin-2-yl)-2H,4'H-3,3'-bi(1,2,4-triazole) (H2pzbtz), in different solvent systems. H2pzbtz shows different geometrical configurations and coordination modes, leading to the diverse three-dimensional (3D) frameworks of 1-3. Complex 1 contains the trinuclear Mn3(tr)4X2 (X = Cl or H2O) clusters and reveals an unobserved (3,4,8)-connected sqc929 topological framework with two types of cages. Complex 2 is a new (3,4,6)-connected network based on dinuclear Mn2(tr)2 clusters, and 3 shows an 8-connected bcu topology with a novel tetranuclear Mn4(tr)6 cluster. Complexes 1 and 2 show antiferromagnetic properties, while 3 reveals spin-canting magnetic behavior with an uncommonly high Tc around 44 K. In addition, 1 also possesses good adsorption selectivity for CO2 over CH4 and N2 and an uncommon gate-opening phenomenon.

C-O/C-H Coupling of Polyfluoroarenes with Aryl Carbamates by Cooperative Ni/Cu Catalysis.

Cross-coupling of polyfluoroarenes with aryl carbamates through the cleavage of both sp(2) C-O and C-H bonds is reported. The reaction conditions are simple, and only transition-metal catalysts and ligands are essential. Mechanistic studies indicated that Ni catalyst played an important role in activating C-O bond, while the Cu one in activating C-H Bond. The developed system proved to be effective for cross-coupling of terminal alkynes with aryl carbamates.

A Cationic MOF with High Uptake and Selectivity for CO2 due to Multiple CO2 -Philic Sites.

The reaction of N-rich pyrazinyl triazolyl carboxyl ligand 3-(4-carboxylbenzene)-5-(2-pyrazinyl)-1H-1,2,4-triazole (H2 cbptz) with MnCl2 afforded 3D cationic metal-organic framework (MOF) [Mn2 (Hcbptz)2 (Cl)(H2 O)]Cl⋅DMF⋅0.5 CH3 CN (1), which has an unusual (3,4)-connected 3,4T1 topology and 1D channels composed of cavities. MOF 1 has a very polar framework that contains exposed metal sites, uncoordinated N atoms, narrow channels, and Cl(-) basic sites, which lead to not only high CO2 uptake, but also remarkably selective adsorption of CO2 over N2 and CH4 at 298-333 K. The multiple CO2 -philic sites were identified by grand canonical Monte Carlo simulations. Moreover, 1 shows excellent stability in natural air environment. These advantages make 1 a very promising candidate in post-combustion CO2 capture, natural-gas upgrading, and landfill gas-purification processes.

A new porous MOF with two uncommon metal-carboxylate-pyrazolate clusters and high CO2/N2 selectivity.

By a less-exploited strategy, a stable framework was constructed by using 4,4'-biphenyldicarboxylic acid (H2bpdc) and methyl-functionalized 3,3',5,5'-tetramethyl-4,4'-bipyrazole (H2bpz) coligands, revealing a new (6,8)-connected net based on two extremely rare trinuclear and tetranuclear metal-carboxylate-pyrazolate clusters. The framework is very porous and possesses not only high CO2 loadings but also very high CO2/N2 selectivities at 308 and 313 K because of the polar pore surface decorated by clusters, pyrazolyl units, and confined cages with methyl groups dangling. Importantly, GCMC simulation identified two favorable CO2 sorption sites located sequentially near Co3(pz)3 and Co3(CO2)2(pz) motifs of the tetranuclear cluster, and the multipoint framework-CO2 interactions were distinguished. The framework also displays remarkable stability toward water and organic solvents.

C60 reduces the bioavailability of mercury in aqueous solutions.

The effects of C60 on mercury bioavailability and sorption were investigated at different C60 dosages, reaction times, and pH ranges using the merR::luxCDABE bioluminescent bioreporter Escherichia coli ARL1. The results demonstrated that the bioavailability of mercury (Hg(2+)) decreased with increasing C60 dosage. Approximately 30% of aqueous mercury became biologically unavailable 2h after interaction with C60 at a mass ratio of C60 to mercury as low as 0.01. However, this reduction in bioavailability plateaued at a mass ratio of C60 to mercury of 10 with a further increase in C60 concentrations resulting in only a 20% additional decrease in bioavailability. If this reduction in bioluminescence output is attributable to mercury sorption on C60, then each one log-order increase in C60 concentration resulted in a 0.86 log-order decrease in the mercury partitioning coefficient (Kd). This relationship implies the presence of high mercury-affinitive sites on C60. The length of reaction time was found to play a more important role than C60 dosage in reducing Hg(2+) bioavailability, suggesting an overall slow kinetics of the C60-Hg interactions. In addition, lowering the pH from 7.2 to 5.8 decreased mercury bioavailability due likely to the increase in mercury's association with C60. These results suggest that C60 may be useful in capturing soluble mercury and thus reducing mercury biotoxicity.

Solvent or temperature induced diverse coordination polymers of silver(I) sulfate and bipyrazole systems: syntheses, crystal structures, luminescence, and sorption properties.

Three new coordination polymers, [Ag4(H2bpz)4(SO4)2]·H2O (1), [Ag2(H2bpz)2(SO4)]·3H2O (2), and [Ag3(H2bpz)4](SO4)2/3(OH)5/3·4H2O (3) have been solvothermally synthesized with Ag2SO4 and flexible ligand 3,3',5,5'-tetramethyl-4,4'-bipyrazole (H2bpz) in different solvents and temperatures. Complex 1 is a 2-fold interpenetrated three-dimensional (3D) framework with an uncommon (3,5)-connected hms topology. Complex 2 is a structural isomer of 1 and shows a three-connected 2D ths net consisting of interesting 3-fold and 2-fold heterochiral helical chains. Complex 3 discloses a grid layer structure, containing heterochiral helical chains and an unusual meso-helix. More interestingly, three sets of layers in 3 stack in different directions, affording an unprecedented 2D + 2D + 2D → 3D polycatenating cationic framework with 1D + 3D porous systems. In 1-3, H2bpz exhibit exobidentate bridging fashions with wide-ranged interpyrazole tilting angles and changeable coordination configurations, such as cis and trans fashions in 1 and 3 and uniform trans fashion in 2. These lead to the isomeric [Ag(H2bpz)]n arrays of wavelike and helical chains in 1 and 2, respectively. Complexes 1-3 display solid-state photoluminescence stemming from the ligand-centered fluorescent emissions of H2bpz. Because of the highly polar framework, 3 shows excellent adsorption selectivity for CO2 over N2.

A 3D porous metal-organic framework containing nanotubes based on multiple helices.

Combining Co2 clusters with mixed H2bpdc and H2bpz ligands creates an unprecedented 3-fold interpenetrated 5-connected porous framework, which possesses the fascinating double-walled nanotubes structure assembled from nonuple and triple helices, and exhibits gas sorption properties.

A polar tetrazolyl-carboxyl microporous Zn(II)-MOF: sorption and luminescent properties.

A Zn(II)-MOF [Zn(2)(tzba)(DMF)]·0.5DMF (1) (H(2)tzba = 4-(1H-tetrazol-5-yl) benzoic acid, DMF = N,N'-dimethylformamide) has been solvothermally synthesized and characterized. 1 is a three-dimensional (3D) microporous framework possessing an unusual multi-nodal (3,3,6)- or (4,4,4,4)-connected topological net. The small-sized pores, open metal sites, phenyl π systems and tetrazolyl groups of tzba(2-) decorating the pore with high polarity enable 1 to attract strongly for CO(2), which leads to high sorption heat for CO(2) and significant selectivities for CO(2) over H(2) and N(2). In addition, 1 and desolvated 1' display strong and weak blue luminescence in solid state, respectively, being mainly related to the framework vibration due to the residing and releasing of DMF molecules in the channel.

Direct lactonization of 2-arylacetic acids through Pd(II)-catalyzed C-H activation/C-O formation.

Palladium-catalyzed direct lactonization of 2-arylacetic acids through a reaction sequence that includes C-H activation/C-O formation is reported. This method provides a concise and efficient pathway to synthesize fully functionalized benzofuranone derivatives, which are highly relevant to bioactive natural and synthetic products.