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Metal organic frameworks (MOFs) are promising porous materials for the adsorption of CO2. Here, we report the study of a luminescent MOF (LMOF), called LMOF-202. We have employed Grand Canonical Monte Carlo (GCMC) simulations to understand and explain the adsorption phenomena inside LMOF-202, and based on the phenomena happening at the molecular level, we have varied the metal ions in LMOF-202 to increase the CO2 affinity and selectivity of the material. We show that the CO2 adsorption capacity and selectivity can be increased by approximately 1.5 times at 1 bar and 298 K by changing the metal ion from Zn to Ba. We also report the feasibility of using this material to capture CO2 from flue gas under realistic conditions (1 bar and 298 K). This work shows that LMOF-202 merits further consideration as a carbon capture adsorbent.

Here, we report the adsorptive removal of trace amounts of dimethyl sulfide (DMS) using metal–organic frameworks (MOFs). Cu2+-based MOFs with open metal sites (OMSs), [Cu3(btc)2] (HKUST-1), where btc = 1,3,5-benzenetricarboxylate, and without OMSs, [Cu2(bdc)2(dabco)] (Cu-JAST-1), where bdc = 1,4-benzenedicarboxylate and dabco = 1,4-diazabicyclo[2.2.2]octane, were investigated for the removal of DMS to compare their performance with that of Ag–Y zeolite, which is currently widely used in industry. HKUST-1 exhibited a considerably higher adsorption capacity for DMS than the other adsorbents, which was confirmed by breakthrough measurements. The adsorption state of DMS with HKUST-1 was directly revealed by single-crystal X-ray diffraction (SXRD) analysis and in situ Raman spectroscopy. In addition, it was shown that DMS can be removed by HKUST-1 even under humid conditions.

Framework flexibility is one of the most important characteristics of metal–organic frameworks (MOFs), making them highly suitable for adsorption applications. There have been a limited number of computational efforts to study flexible MOFs in the literature, and they are mostly focused on MIL-53. We studied a flexible MOF known as LMOF-201, which was found to exhibit guest-induced flexible properties; however, the mechanism of the appearance of flexibility is still unclear. First, we validated our simulation results by reproducing the experimental isotherm and powder X-ray diffraction measurements of experimental structures using grand canonical Monte Carlo (GCMC) and reactive force field (ReaxFF) molecular dynamics (MD) simulations. Then, we demonstrated the importance of the presence of a carbonyl oxygen atom in LMOF-201 to induce flexibility. The mechanism determined in this study will enable LMOF-201 to be considered for adsorption applications in the future.

Development of proton conduction materials with a high performance via functionalization of porous coordination polymers (PCPs) is challenging yet promising. Herein, a facile and efficient method t...

Cobalt sulfides (including CoS, CoS2, Co3S4, Co9S8 and nonstoichiometric Co1−xS) are deemed to a kind of novel anode material for lithium ion batteries due to their large specific capacities. However, cobalt sulfides suffer from poor cycling stability with the large volume expansion. In this work, we designed and synthesized a novel Co-metal organic frameworks (MOFs) material by using carbazolyl carboxylates ligand H4DCDC. The Co1−xS nanoparticles embedded in N-doped carbon sheets (Co1−xS/NCS) composites are obtained via vulcanizing the Co-MOFs precursor. As a result, the Co1−xS/NCS exhibits outstanding cycling stability and maintains a high capacity of 796.3 mA h g−1 at the current density of 200 mA g−1 after 100 cycles. The N-doped carbon sheets can not only enhance the conductivity of materials but also buffer the volume expansion during charge-discharge process.

In this study, we report a facile ligand-assisted in situ hydrothermal approach for preparation of compact [Al(OH)(1,4-NDC)] (1,4-NDC=1,4-naphthalenedicarboxylate) MOF membranes on porous γ-Al2 O3 substrates, which also served as the Al3+ source of MOF membranes. Simultaneously, it was observed that the heating mode exerted significant influence on the final microstructure and separation performance of [Al(OH)(1,4-NDC)] membranes. Compared with the conventional hydrothermal method, the employment of microwave heating led to the formation of [Al(OH)(1,4-NDC)] membranes composed of closely packed nanorods with superior H2 /CH4 selectivity.

Solvothermal reactions of CdCl2·2.5H2O and 1,4-benzenedicarboxylic acid (1,4-H2bdc) with 1,3-bis(1-imidazolyl)-5-[2-(1-imidazolyl)-phenoxymethyl]-benzene (otim), 1,3-bis(1-imidazolyl)-5-[3-(1-imidazolyl)-phenoxymethyl]-benzene (mtim) or 1,3-bis(1-imidazolyl)-5-[4-(1-imidazolyl)-phenoxymethyl]-benzene (ptim) at 150 °C gave rise to three cadmium(II) coordination polymers [Cd3(1,4-bdc)3(otim)2(H2O)]n (1), {[Cd(1,4-bdc)(mtim)]·0.5H2O}n (2) and {[Cd(1,4-bdc)(ptim)]·1.5H2O}n (3). Complexes 1–3 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. In Compound 1, 3D [Cd(otim)]n units are reinforced by 1D helical chains [Cd(1,4-bdc)]n, resulting in 3-fold interpenetrating 3D framework. Compound 2 exhibits a 4-fold interpenetrating 3D framework formed by linking ladderlike [Cd(mtim)]n units with two pairs of 1,4-bdc bridges. Compound 3 can be considered as a 2-fold interpenetrating 3D pillared-layer framework in which 2D [Cd(ptim)]n layers are interconnected by 1,4-bdc pillars. The Schlafli symbols for these three 3D nets are (5·102)(5·7·82·102) (1), (42·6)(42·65·83) (2), and (63)(69·8) (3). The formation of 1–3 provided an interesting insight into coordinated group site effect on the construction of Cd(II)/tri-imidazolyl/dicarboxylate CPs under solvothermal conditions. The solid state luminescent properties of 1–3 at ambient temperature were also investigated, and 3 showed a high selectivity and sensitivity for acetone because of the quenching effect.

Triplet carbenes (TCs) are of great interest due to their magnetic properties and reactivity, which descend from TCs' unique electronic state. However, the reactivity and stability of TCs are usually a trade-off, and it is difficult to achieve both at the same time. In this work, we were able to enhance the thermal stability of a TC species while maintaining its reactivity by confining them in the nanospace of a metal-organic framework (MOF). We synthesized a new MOF using a TC precursor; subsequently, TCs were generated by photostimulation. The TCs generated in the MOF nanospace were detectable up to 170 K, whereas their non-MOF-confined counterparts (bare ligand) could not be detected above 100 K. In addition, the reactivity of TC generated in MOF with O2 was drastically improved compared to that of bare ligand. Our approach is generally applicable to the stabilization of highly reactive species, whose reactivity needs to be preserved.

In comparison with the fast development of binary mixture separations, ternary mixture separations are significantly more difficult and have rarely been realized by a single material. Herein, a new strategy of tuning the gate-opening pressure of flexible MOFs is developed to tackle such a challenge. As demonstrated by a flexible framework NTU-65, the gate-opening pressure of ethylene (C2H4), acetylene (C2H2), and carbon dioxide (CO2) can be regulated by temperature. Therefore, efficient sieving separation of this ternary mixture was realized. Under optimized temperature, NTU-65 adsorbed a large amount of C2H2 and CO2 through gate-opening and only negligible amount of C2H4. Breakthrough experiments demonstrated that this material can simultaneously capture C2H2 and CO2, yielding polymer-grade (>99.99 C2H4 from single breakthrough separation.

Molecular motions taking place in the nanospace of metal–organic frameworks (MOFs) are an interesting research subject, although not yet fully investigated. In this work, we utilized in situ Raman spectroscopy in the ultralow-frequency region to investigate the libration motion (including the rotational motion of phenylene rings) of MOFs, in particular [Cu2(bdc)2(dabco)] (Cu-JAST-1), where bdc = 1,4-benzenedicarboxylate and dabco = 1,4-diazabicyclo[2.2.2]octane. The libration mode of Cu-JAST-1 was found to be significantly suppressed by the adsorption of various guest molecules, such as CO2, Ar, and N2. In addition, an appreciable correlation between the libration mode and adsorption equilibrium time was identified, which provides useful novel tools in the design of MOFs acting as molecular adsorption and separation materials.

We developed a facile one-step dialysis method to prepare a series of hollow iridium complexes and their rare-earth hybrid complex nanoparticles (NPs). The resulting Ir–Dy hybrid NPs exhibited an excellent transverse relaxivity (r2) value of ∼194.5 mM−1 s−1 (7.0 T) and a strong ultrasound contrast effect with the signal stable up to 10 min.

We report herein convenient access to tetranuclear clusters of [Ln4(RPO3)2(RPO3H)(tBuCO2)7(tBuCO2H)3(H2O)3]·solvent Ln4 (Ln = Gd, Dy), from dinuclear lanthanide precursors [Ln2(O2CtBu)6(HO2CtBu)6] and a bulky phosphonate ligand (9-methyl-9H-fluoren-9-yl)phosphonic acid (RPO3H2). In the structures of Ln4, four Ln(III) ions are arranged at the vertices of an irregular quadrilateral that are wrapped by bulky hydrophobic fluorenyl groups. Magnetic studies show that Gd4 exhibits high magnetocaloric effect (MCE) with entropy change of 23.10 J kg−1 K−1 at 2.5 K for ΔH = 7 T, while Dy4 shows slow magnetic relaxation that is the character of a single-molecule magnet (SMM).

A new coordination network based on 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid (H2bismip) along with 4,4-bis(1-imidazolyl)bibenzene (bimb), formulated as [Ni2(bismip)2(bimb)2(H2O)]n (1) has been synthesized under solvothermal condition. Compound 1 has been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD). Single crystal X-ray diffraction analysis shows compound 1 is a 2D network with a Schlafli symbol of 44. The layer framework exhibits effective adsorption on organic dye. The kinetic of the adsorption process was analyzed by the pseudo-first-order and pseudo-second-order model equations and the data was fitted well with the pseudo-second-order kinetic model (R > 0.99). The compound was found to be an excellent selective absorbent for the removal of methyl orange (MO) from the mixture solution of methyl orange - methylene blue (MO-MB).

In this study, it was demonstrated that the introduction of Co–Al/Mg–Al hydrotalcite-like compound buffer layers on porous α-Al2O3 substrates enabled effective manipulation of the microstructure of ZIF-7 films so that metal ions located in the inorganic buffer layers were not necessarily identical with those residing in the MOF crystals. Moreover, zinc sources were found to exert a significant influence on the final microstructure of the prepared ZIF-7 films. In addition to ZIF-7, well-intergrown ZIF-8 and HKUST-1 films could also be in situ grown on diverse HTlc buffer layer-modified α-Al2O3 substrates, which convincingly demonstrated the generality of this strategy for the facile preparation of qualified MOF films/membranes.

Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization method. Through transmission electron microscopy, powder X-ray diffraction, and X-ray photoelectron spectroscopy, the role of the carbon supports for the catalytic performances of Pd/C catalysts was examined in selective hydrogenation of acetylene. The results indicate that Pd/AC exhibited higher activity and selectivity than Pd/GO and Pd/rGO in the gas phase selective hydrogenation of acetylene. Thermal and chemical treatment of AC supports also have some effect on the catalytic performance of Pd/AC catalysts. The differences in the activity and selectivity of various Pd/C catalysts were partly attributed to the metal-support interaction.Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization method. Through transmission electron microscopy, powder X-ray diffraction, and X-ray photoelectron spectroscopy, the role of the carbon supports for the catalytic performances of Pd/C catalysts was examined in selective hydrogenation of acetylene. The results indicate that Pd/AC exhibited higher activity and selectivity than Pd/GO and Pd/rGO in the gas phase selective hydrogenation of acetylene. Thermal and chemical treatment of AC supports also have some effect on the catalytic performance of Pd/AC catalysts. The differences in the activity and selectivity of various Pd/C catalysts were partly attributed to the metal-support interaction.

Reaction in well-designed solids allows yielding products with high selectivity and unique compounds that cannot be obtained in solution. However, the precise tuning of the arrangement of reactants in solids for the versatile application of solid-phase reactions remains a challenging subject. Here, a [2 + 2] photocyclization reaction at different positions of the carbon-carbon bonds is described in which the spatial arrangement of 4-styrylpyridines (4-spy) is changed by guest molecules in a flexible metal-organic framework. The 4-spy molecules undergo photodimerization between two carbon-carbon double bonds in the guest-free framework, whereas a reaction between olefinic and aromatic carbon-carbon bonds or the absence of reaction takes place in the solvent-incorporated form. This reactivity, which can be termed as "dynamic topochemistry" contributes to enforce the applicability of solid-phase reactions in synthetic chemistry.

Various Au/GO catalysts were prepared by depositing Au nanoparticles on thermally- and chemically-treated graphite oxide (GO) supports using a sol-immobilization method. The surface chemistry and structure of GO supports were characterized by a series of analytical techniques including X-ray photoelectron spectroscopy, temperature-programmed desorption and Raman spectroscopy. The results show that thermal and chemical treatments have large influence on the presence of surface oxygenated groups and the crystalline structure of GO supports. A strong support effect was observed on the catalytic activity of Au/GO catalysts in the liquid phase aerobic oxidation of benzyl alcohol. Compared to the amount and the type of surface oxygen functional groups, the ordered structure of GO supports may play a more important role in determining the catalytic performance of Au/GO catalysts.

[Zn2(FDC)2(bpy)] (LMOF-202) and [Zn2(OFDC)2(bpy)] (LMOF-201) (FDC: fluorene-2,7-dicarboxylate, OFDC: 9-fluorenone-2,7-dicarboxylate, bpy: 4,4′-bipyridine) have interpenetrated isostructures. However, their gas sorption behaviors indicate that LMOF-202 is rigid, whereas LMOF-201 is flexible. We found that the structural flexibility of LMOF-201 was due to the addition of only one oxygen atom into the ligand.

The building of 3d-Gd clusters are very essential in the fields of magnetic refrigerants. Three bulky phosphonic acids: (9-methyl-9H-fluoren-9-yl)phosphonic acid ( R PO 3 H 2 ), (2,7-di-tert-butyl-9-methyl-9H-fluoren-9-yl)phosphonic acid ( R ′PO 3 H 2 ), and (9-(sec-butyl)-2,7-di-tert-butyl-9H-fluoren-9-yl)phosphonic acid ( R ″PO 3 H 2 ) have been employed to construct four Co II -Gd III clusters [Co II 2 Gd III 3 (OH)( R PO 3 ) 2 ( t BuCO 2 ) 8 ( t BuCO 2 H) 2 (C 5 H 5 N)(H 2 O) 2 ]·2H 2 O· t BuCO 2 H ( 1 ), [Co II 4 Gd III 3 (OH) 2 ( R PO 3 ) 2 ( t BuCO 2 ) 11 (py)(CH 3 CN)(H 2 O) 2 ]⋅CH 3 CN ( 2 ), [Co II 3 Gd III 3 (OH) 2 ( R ′PO 3 ) 2 ( t BuCO 2 ) 9 ( t BuCO 2 H)(H 2 O) 2 ]· t BuCO 2 H·2CH 2 Cl 2 ( 3 ) and [Co II 3 Gd III ( R ″PO 3 ) 2 ( t BuCO 2 ) 5 (CH 3 CN)(H 2 O) 4 ]· t BuCO 2 H·3CH 3 CN ( 4 ) under ambient condition. Clearly, the varied hindrance of fluorenyl groups are responsible for the formation of various clusters. Single crystal analysis indicates that the metal ions arrange in one plane in each cluster. Magnetic studies show that the entropy changes are 18.3, 19.8, 20.0 and 9.6 J kg −1 K −1 for 1 – 4 , respectively, from which we can see these values are nearly proportional to the percentage of the gadolinium in the core.

Five nickel coordination polymers, {[Ni(bismip)(2,2′-bipy)(H2O)]·H2O}n (1), {[Ni(bismip)(phen)]·3H2O}n (2), [Ni(bismip)(im)]n (3), {[Ni(bismip)(4,4′-bipy)(H2O)2]·3·5H2O}n (4) and {[Ni(bismip)(bpp)(H2O)]·H2O}n (5) (H2bismip = 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, 2,2′-bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline, im = imidazole, 4,4′-bipy = 4,4′-bipyridine, bpp = 1,3-bis(4-pyridyl)propane) have been synthesized under solvothermal conditions. Compounds 1–5 have been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD) and single crystal X-ray diffraction analysis. 1–3 represent 3D supermolecules based on their respective 1D chains through hydrogen-bonding interactions. 4 reveals a 3D architecture composed of 2D regular grids through hydrogen-bonding interactions. 5 is a 3D framework with 2D undulating nets inclined polycatenation. Thermal stabilities and photocatalytic properties of 1–5 in the solid state were also investigated.

Three cadmium coordination polymers, [Cd(bismip)]n (1), {[Cd(bismip)(phen)]·H2O}n (2) and {[Cd2(bismip)2(4,4′-bipy)]·2H2O}n (3) (H2bismip=5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, phen=1,10-phenanthroline, 4,4′-bipy=4,4′-bipyridine) have been prepared under solvothermal conditions. In 1, the [Cd4(bismip)3] units are jointed by bismip ligands to afford a three-dimensional (3D) architecture. Complex 2 exhibits a 3D supramolecular framework based on the interconnection of 1D chains through hydrogen bonding interactions and π-π packing interactions. 3 is a two-fold interpenetrating 3D architecture with a (4·82)(42·84) Schlafli symbol in which 2D layers are interlinked by 4,4′-bipy ligands. The diverse structures of compounds 1–3 indicate that the auxiliary ligands have significant effects on the final structures. The photoluminescent properties and photocatalytic properties of these coordination polymers in the solid state were also investigated. Remarkably, 3 shows the wide gap semiconductor nature and exhibit excellent photocatalytic performance.

The study on structure–property relationships of polynuclear 3d-Gd clusters are very essential in the fields of magnetic refrigerants. We designed two new bulky phosphonic acids: (3-(9H-carbazol-9-yl)propyl)phosphonic acid (CarbpPO3H2) and (2-(9-methyl-9H-fluoren-9-yl)ethyl)phosphonic acid (FlumePO3H2). Based on these ligands, two clusters [Co(II)4Gd(III)6(CarbpPO3)6(tBuCO2)14(tBuCO2H)(H2O)3].9CH3CN.CH2Cl2 (1) and [Co(II)4Gd(III)6(FlumePO3)3(tBuCO2)14(μ3-OH)6(H2O)2(CH3CN)].6CH3CN (2) were synthesized under ambient condition. Compound 1 has a [3 × 3] grid-like structure, while compound 2 has a rare helmet-like cage structure. The magnetocaloric effect (MCE) have been tuned from 22.83 to 29.06 J kg−1 K−1 as the molecular structure changes from grid to cage.

Nanoporous materials can adsorb small molecules into their nanospaces. However, the trapping of light gas molecules dissolved in solvents suffers from low concentration and poor adsorption affinity. Here, the reversible trapping and releasing of dissolved oxygen are shown through integrating photosensitization and chemical capturing abilities into a metal-organic framework (MOF), MOMF-1. 9,10-Di(4-pyridyl)anthracene (dpa) ligands in MOMF-1 generates singlet oxygen from triplet oxygen under photoirradiation without additional photosensitizers, and successively reacts with it to produce anthracene endoperoxide, forming MOMF-2, which is proved crystallographically. The reverse reaction also proceeds quantitatively by heating MOMF-2. Moreover, MOMF-1 exhibits excellent water resistance, and completely removes oxygen of ppm order concentrations in water. The new material shown in this report allows controlling of the amount of dissolved oxygen, which can be applicable in various fields relating to numerous oxidation phenomena.

Metal-organic frameworks (MOFs) have received continuous attention because of their highly porous, diversified structures and potential applications as novel adsorbents. In this chapter, the recent progress in developing MOFs for CO2 capture is reviewed. Several strategies being used to improve CO2 adsorption uptake at low pressure are highlighted. These strategies are generation of interaction sites in the pores as well as controlling of pore size of MOFs, building of flexible MOFs, and construction of water-stable MOFs. In addition, the high-pressure CO2 adsorption in highly porous MOFs is reviewed. At last, the studies of CO2-loaded structures with crystallographic technique are summarized.

Herein, we developed isostructural metal-organic frameworks (MOFs) [Cu1-xPdx(SiF6)(bpy)2] (bpy: 4,4'-bipyridine) (SIFSIX-1-CuPd-3, -5 and -10) containing open metal sites using a partial metal-replacement approach. Starting from the SIFSIX-1-Cu-type MOF, some of the Cu2+ ions having octahedral geometry were successfully replaced with Pd2+ ions having square planar geometry in different ratios, while the framework structure was maintained. The results showed that gas adsorption properties of SIFSIX-1-Cu-type MOFs can be tuned via partial metal replacement.

1D manganese carboxylates [Mn(mfa)2(H2O)]n (1) and {[Mn3(mfp)6(CH3OH)2]·2CH3OH}n (2) (Hmfa = 2-(9-methyl-9H-fluoren-9-yl)acetic acid, Hmfp = 3-(9-methyl-9H-fluoren-9-yl)propanoic acid) were synthesized by reactions of Mn(ClO4)2·6H2O and the corresponding carboxylate. In compound 1, the Mn(II) ions are bridged by two carboxylate groups in μ2-η1,η1 and μ2-η2,η1 bridging modes into one uniform chain. Compound 2 has a distinctive chainlike structure contrast to compound 1, that are constructed alternatively from mononuclear Mn(II) and dinuclear [Mn2(mfp)2(CH3OH)2] units by two μ2-η1,η1-carboxylates and one O atom from the third carboxylate ligand. Magnetic susceptibility measurements revealed a weak antiferromagnetic coupling for both complexes. The magnetic data were fitted by using uniform chain and –AF1–AF1–AF2– antiferromagnetic chain models for 1 and 2, respectively.

The bulky phosphonate ligands CarbmPO3H2 (((9H-carbazol-9-yl)methyl)phosphonic acid) and CarbePO3H2 ((2-(9H-carbazol-9-yl)ethyl)phosphonic acid) were employed to construct cages [Ni9{(py)2CO2}2(CarbmPO3)4(tBuCO2)6(tBuCO2H)2(CH3CN)2] 1 and [Ni11{(py)2CO2}2(CarbePO3)4(tBuCO2)10(CH3CN)2] 2 with (py)2CO (di-2-pyridyl ketone) and Hpiv (pivalic acid) as coligands under solvothermal conditions. The metallic cores of cages 1 and 2 display vertex-sharing tetragonal pyramidal and tetra-capped octahedral arrangements, respectively. Magnetic property measurements indicate the coexistence of antiferromagnetic and ferromagnetic interactions between nickel centers for both cages.

Hydrothermal reactions of Zn(NO3)2·6H2O or CdCl2·2.5H2O with bis-(4-imidazol-1-yl-phenyl)-amine (bimpa) and 5-methyl-1,3-benzenedicarboxylic acid (5-Me-1,3-H2BDC) or 5-tert-butyl-1,3-benzenedicarboxylic acid (5-tb-1,3-H2BDC) afforded four coordination polymers, [Zn2(5-Me-1,3-BDC)2(bimpa)2]n (1), {[Cd2(5-Me-1,3-BDC)2(bimpa)(H2O)4]·H2O}n (2), {[Zn(5-tb-1,3-BDC)(bimpa)]·2H2O}n (3) and {[Cd(5-tb-1,3-BDC)(bimpa)]·H2O}n (4). Complexes 1–4 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. 1 exhibits a 4-fold interpenetrating 3D framework in which 1D curvilinear chains are interconnected by bimpa ligands. 2 can be considered as a 3D supramolecular architecture based on 2D entanglements which consist of 1D tubes in parallel interpenetration. 3 and 4, respectively, have 2D (65·8) layers (3) and 2D layers constructed by 1D tubes (4), which are further extended into two 3D supramolecular architectures through weak hydrogen-bonding and π⋯π interactions. The solid state luminescence and optical properties of 1–4 at ambient temperature were also investigated. A comparative study on their photocatalytic activity toward the degradation of methylene blue in polluted water was explored.

A simple and efficient procedure for the synthesis of amides directly from aldehydes and amines catalyzed by heteropolyanion-based ionic liquids under solvent-free conditions has been reported. The practical protocol was found to tolerate a wide range of substrates with different functional groups. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. The proposed dual-catalysis mechanistic pathway was briefly investigated. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this oxidative amidation.

Direct observation of gas molecules confined in the nanospace of porous materials by single-crystal X-ray diffraction (SXRD) technique is significant because it leads to deep insight into the adsorption mechanism and the actual state of the adsorbents in molecular level. A recent study revealed that flexibility is one of the important factors to achieve periodic guest accommodation in the nanospace enabling direct observation of gas molecules. Here, we report a convenient strategy to tune the framework flexibility by just an atomic exchange in a ligand, which enables us to easily construct a soft nanospace as the best platform to study gas adsorption. Indeed, we succeeded to observe C2H2 and CO2 molecules confined in the pores of a flexible porous coordination polymer (PCP-N) in different configurations using SXRD measurement, whereas gas molecules in a rigid framework (PCP-C) isostructural to PCP-N were not seen crystallographically. The result of the coincident in situ powder X-ray diffraction and adsorption measurement for PCP-N unambiguously showed that the framework could flexibly transform to trap gas molecules with a commensurate fashion. In addition, for PCP-N, we found that the adsorbed gas molecules induced significant structural change involving dimensional change of the pore from one-dimensional to three-dimensional, and subsequently, additional gas molecules formed periodic molecular clusters in the nanospace.

A simple and efficient procedure for the synthesis of amides directly from unactivated esters and amines catalyzed by heteropolyanion-based ionic liquids under microwave-promoted and solvent-free conditions has been reported. The practical protocol was found to be compatible with different structurally diverse substrates. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this amidation.

Reactions of carbazol-9-ylpropanate (carbp−) with manganese perchlorate in the presence of 2,2′-bipy and 4,4′-bipy yield four compounds, namely, [Mn2(carbp)2(2,2′-bipy)4](ClO4)2 (1), [Mn2(carbp)2(4,4′-bipy)4](ClO4)2 (2), [MnII4MnIII2(μ4-O)2(carbp)10(DMF)4] (3) and [MnII4MnIII2(μ4-O)2(carbp)10(4,4′-bipy)2] (4). Compound 1 and 2 have dinuclear structures, in which the MnII ions are linked by two carbp− bridges. Compound 3 has a hexanuclear structure, in which two MnIII ions are surrounded by four MnII ions to form two edge-sharing OMn4 tetrahedra giving rise to the [MnII4MnIII2(μ4-O)2]10+ core. While, compound 4 has a 3-D porous structure with [MnII4MnIII2(μ4-O)2(carbp)10] as node and 4,4′-bipy as spacer. Magnetic susceptibility measurements show the presence of dominant antiferromagnetic interactions in compounds 1–4.

Three zinc(II) carboxyphosphonates [Zn3(5-pmipe)2]·0.5H2O (1·0.5H2O), [Zn3(5-pmipm)2]·H2O (2·H2O), and [Zn3(5-pmipH)2(bpy)0.5]·6H2O (3·6H2O) (5-pmipH4 = 5-(phosphonomethyl)isophthalic acid, 5-pmipeH3 = [C6H3(CO2H)(CO2Et)(CH2PO3H2)], 5-pmipmH3 = [C6H3(CO2H)(CO2Me)(CH2PO3H2)], bpy = 4,4′-bipyridine) were synthesized under hydrothermal conditions. Compounds 1 and 2 are isostructural. In compounds 1 and 2, the {ZnO4} and {CPO3} tetrahedra are interconnected into a zigzag infinite chain via corner-sharing. In addition, these chains are further linked by carboxyphosphonate ligands into a 2D layer. Interestingly, one carboxylate group experiences an in situ esterification reaction with ethanol and methanol, respectively. Compound 3 displays a 3D pillared-bilayer open framework structure. The {ZnO4}, {ZnO3N} and {CPO3} tetrahedra are interlinked through corner-sharing into one chain, which are joined together by 5-pmipH3− into a bilayer. The layers are pillared up by bpy into 3D network. The luminescent properties of compounds 1–3 were investigated in solid state at room temperature.

Background: Evidences have shown that the RAS signalling pathway plays an important role in colorectal cancer (CRC). Moreover, RAS-GTPase-activating proteins (RASGAPs) as RAS signalling terminators are associated with tumourigenicity and tumour progression. In this study, we used bioinformatics analysis to predict and study important miRNAs that could target RAS p21 GTPase-activating protein 1 (RASA1), an important member of RASGAPs. Methods: The levels of RASA1 and miR-223 were analysed by real-time PCR, western blotting or in situ immunofluorescence analyses. The functional effects of miR-223 and the effects of miR-223-targeted inhibitors were examined in vivo using established assays. Results: Upregulation of miR-223 was detected in CRC tissues (P

A Zn(II)-based porous coordination polymer (PCP) {[Zn2(ppt)2(fdc)(H2O)2]·2DMF}n (1) (H2fdc = 9H-fluorene-2,7-dicarboxylic acid, Hppt = 3-(2-pyrazinyl)-5-(4-pyridyl)-1,2,4-triazole) has been synthesized under hydrothermal conditions. The resulting PCP shows a 7-fold interpenetrated 3D structure that can be simplified as a diamond-like structure with Zn1 as node and fdc− and Zn(ppt)2 as spacers. It exhibits strong luminescence at room temperature in solid-state. Luminescent property study shows that 1 can be used as a fluorescent sensor for nitrobenzene (NB).

Four new coordination polymers, {[Zn(bismip)]·2H2O}n (1), {[Zn2(bismip)2(4,4′-bipy)]·2H2O}n (2), {Zn2(bismip)2(phen)}n (3) and {[Zn(bismip)(bimb)]2·2H2O·DMF}n (4) (H2bismip = 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid, 4,4′-bipy = 4,4′-bipyridine, phen = 1,10-phenanthroline, bimb = 4,4-bis(1-imidazolyl)bibenzene) were synthesized under solvothermal conditions. All these compounds were characterized by elemental analysis, IR spectroscopy, thermal analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Compound 1 features a two-dimensional (2D) binodal (3,6)-connected kgd network with (43)2(46·66·83) topology. 2 exhibits two-fold interpenetrating 3D architecture with a (4·82)(42·84) Schlafli symbol in which 2D layers are interlinked by 4,4-bipy ligands. In 3, the [Zn4(bismip)4] and [ZnO4N2] units are interconnected, affording a binodal 3D (3,4)-connected network with the Schlafli symbol (83)(86). 4 is a 2D (3,4)-connected coordination network with (42·6)(42·63·8) topology. The photoluminescence properties and photocatalytic properties of these compounds were also investigated.