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Three imidazole-modified Ag-polyoxovanadates frameworks (APFs) with a controllable molar ratio of Ag+ to polyoxovanadates (POVs) [Ag(IM)2]2V4O12∙2Ag(IM)2 (APF-1), [Ag2(1-eIM)4]2[Ag(1-eIM)2]3∙2Ag(1-eIM)2∙3(1-HeIM)[V10O28]2 (APF-2) and [Ag(1-pIM)2]3[HV10O28]∙2Ag(1-pIM)2∙2H2O (APF-3) (IM = imidazole; 1-eIM = 1-ethylimidazole and 1-pIM = 1-propylimidazole) have been successfully achieved by self-assembly of POVs, Ag+ cations, and three different imidazole derivatives. Interestingly, the molar ratios of Ag+ to POVs vary from 4:1, 4.5:1 to 5:1 by changing the vanadium resources and imidazole derivatives. Notably, the coordination environment of Ag+ cations and the structure of POVs in the APFs are also different. Specifically, for APF-1, the four Ag atoms adopt three-coordinated and four-coordinated geometries, respectively, and Ag-imidazole complexes and [V4O12]4− cluster form the one-dimensional polymeric chains. While Ag atoms in APF-2 and APF-3 exhibit two-, four- and five-coordinated geometries for APF-2, four-, five- and six-coordinated geometries for APF-3, respectively. These Ag+ cations and decavanadate clusters are assembled into the 2D supramolecular structure through the Ag-O bonds and Ag…Ag argentophilic interaction. Remarkably, thus-obtained APF-2 can serve as powerful efficient heterogeneous catalyst for construction of C-N bond and detoxification of simulant sulfur mustard (yields up to 99%), which enable successful recycling for three cycles with remained catalytic activities and structure stability.

Guided by a second-sphere interaction strategy, we fabricated a Tb(III)-based metal-organic framework (MMCF-4) for turn-on sensing of methyl amine with ultra-low detection limit and high turn-on efficiency. MMCF-4 features lanthanide nodes shielded in a nonacoordinate geometry along with secondary coordination spheres that are densely populated with H-bond interacting sites. Nonradiative routes were inhibited by binding-induced rigidification of the ligand on the second coordination sphere, resulting in luminescence amplification. Such remote interacting mechanism involved in the turn-on sensing event was confirmed by single-crystal X-ray diffraction and molecular dynamic simulation studies. The design of both primary and secondary coordination spheres of Tb(III) enabled the first turn-on sensing of organic amines in aqueous conditions. Our work suggests a promising strategy for high-performance turn-on sensing for Ln-MOFs and luminous materials driven by other metal chromophores.

Simple reaction conditions and recyclable reagents are crucial for environmentally friendly industrial applications. An environment-friendly, recyclable and economic strategy was developed to synthesize diaryl chalcogenides by the CuCl2-catalyzed C–S bond-formation reaction via iodobenzenes and benzenethiols/1,2-diphenyldisulfanes using N,N′-dimethylethane-1,2-diamine (DMEDA) as ligand, base, and solvent. For these reactions, especially the reactions of diiodobenzenes and aminobenzenethiols/disulfanediyldianilines, a range of substrates are compatible and give the corresponding products in good to excellent yields. Both of the reagents in the catalytic system (CuCl2/DMEDA) are inexpensive, conveniently separable, and recyclable for more than five cycles.

Summary γ-butyrolactone (γ-BL), serving as the monomer of biocompatible and recyclable poly(γ-butyrolactone) plastic, faces a giant challenge in ring-opening polymerization (ROP) due to its low strain energy. The ROP of γ-BL is generally achieved under harsh conditions (e.g., high-pressure or gas-protected atmosphere) and is mostly based on homogeneous systems. Here, we synthesize a series of lanthanum metal-organic framework-based porous nanospheres and successfully apply them as heterogeneous catalysts in efficient ROP of γ-BL under mild conditions. Specifically, NNU-mIM-3 presents a yield of 24.6% with low polydispersity distribution centered at 3.6 kDa and the obtained PγBL can be completely and quantitatively recycled into monomers by simple heat treatment. Besides, the ROP catalysis systems have been intensively explored with various imine-based additives, proven to exhibit largely improved performance with PγBL yield of ~50% and Mw of ~8 kDa. This work paves a new way to explore novel heterogeneous catalysts in producing biocompatible and degradable plastics.

By introducing 4-amino-1,2,4-triazole (4-NH2-trz), three new polyoxovanadate-based metal-organic frameworks (PMOFs) [Ni3(4-NH2-trz)6][V6O18]·3H2O (1), [Co3(4-NH2-trz)6][V6O18]·3H2O (2) and [Cu3OH(4-NH2-trz)3H2O][VO3]5·H2O (3) have been synthesized and thoroughly characterized by single-crystal X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), thermogravimetric (TG) analysis and elemental analysis (EA). Among them, PMOFs 1 and 2 had similar structures containing [V6O18]6- clusters; however, PMOF 3 was isolated as a structure containing a [VO3]55- cluster when the amount of the 4-NH2-trz ligand was reduced to half with the other synthesis conditions being the same as those of PMOFs 1 and 2 except for the transition-metal chlorides. Furthermore, the negative charges of polyoxovanadate [V6O18]6- and [VO3]55- anions were balanced by trinuclear complex cations [Ni3(4-NH2-trz)6]6- for 1, [Co3(4-NH2-trz)6]6- for 2 and [Cu3OH(4-NH2-trz)3H2O]5- for 3, respectively. PMOFs 1-3 were further used as heterogeneous catalysts in the Knoevenagel condensation under solvent-free conditions and showed high catalytic activity. PMOF 1 showed moderate catalytic activities in the oxidation of various aromatic alcohols using H2O2 as an oxidant. Moreover, PMOF 1 could be reused at least three times without losing its activity.

Polyoxometalates (POMs) is a kind of metal-oxygen clusters with well-defined structures, controllable composition, and excellent properties including acidity, redox properties, etc . In recent years, POMs have shown potential application in the field of catalysis, materials, energy conversion and pharmaceuticals and become a hot interdisciplinary research area. This review focuses on the recent progress in the structure design of POMs and their catalytic properties, mainly including POM structure chemistry, acid-base catalysis, redox catalysis, photocatalysis, the catalytic conversion of CO2 and toxic molecules. In addition, the future development of POMs-based catalysis is prospected.

A series of microporous Ln(III)-based metal–organic frameworks (1-Ln) have been hydrothermally synthesized using 4,4′,4′′-nitrilotribenzoic acid (H3NTB). Single crystal X-ray diffraction analyses show that 1-Ln are isostructural and have 3D porous frameworks with remarkable stability and permanent porosity for Ar and CO2 adsorption. In addition, 1-Ln exhibit diverse photoluminescence emissions depending on the nature of lanthanide ions. More importantly, 1-Ln are further studied in the Knoevenagel reactions of benzaldehyde derivatives and malononitrile under solvent-free conditions, and it is found that 1-Tb shows the best catalytic activities (yields up to 99%), providing a unique example to differentiate the roles of Ln ions within the frameworks in catalyzing Knoevenagel reactions.

We reported an economic and practical ball-milling method for the synthesis of tetrahydroquinoline derivatives via a ‘one-pot’ three-component Diels-Alder reaction of anilines, aldehydes and alkenes catalyzed by phosphotungstic acid at room temperature. For this reaction, a simple “one-pot” ball-milling operation was conducted, readily available starting materials were employed, ‘one-pot’ conditions were applied, and the most important was to use inexpensive and environmentally friendly catalyst phosphotungstic acid. Various tetrahydroquinolines, which might be potentially applicable in the pharmaceutical and biochemical areas, were conveniently synthesized in moderate to excellent yields.

One bonded- and one discreted-Lindqvist hexatungstate-based copper hybrids (Cu-POMs) ([Cu2(O)OH(phen)2]2[W6O19]·6H2O (1) and [Cu2(phen)4Cl] [HW6O19]·2H2O (2) (phen = 1,10-phenanthroline)) were controllably synthesized and routinely characterized. Cu-POMs 1–2 consisted of identical [W6O19] unit and similar copper–phen complexes, the two units are bonded via four Cu–O chemical bonds in compound 1; however, compound 2 is discreted and stabilized by intermolecular electrostatic interactions. Importantly, these Cu-POMs catalysts were first applied in the novel reaction for the preparation of 2-phenylquinoxalines via the one-pot coupling and oxidation reactions of 2-haloanilines with vinyl azides or 3-phenyl-2H-azirines under mild conditions, and Cu-POMs 1 showed higher catalytic performance in good yields (79–84%). The reactions exhibit some functional group tolerance and allow for the preparation of a number of 2-phenylquinoxalines.

By rationally controlling hydrothermal conditions, three new inorganic–organic hybrid polyoxovanadates (POVs) [Ni2(1-vIM)7H2O][V4O12]·H2O (1), [Cu2(1-vIM)8][V4O12]·H2O (2) and [Co(1-vIM)H2O][VO3]2 (3) (1-vIM = 1-vinylimidazole) have been synthesized and thoroughly characterized by single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR), and elemental analyses (EA). Interestingly, complexes 1 and 2 have similar structures including [V4O12]4− clusters; complex 3, however, was isolated as a structure by including the [VO3]22− cluster under a different synthetic condition compared with those of 1 and 2. Both complexes 1 and 2 display an interesting 3D supramolecular structure, and complex 3 shows a 2D two parallel networks supramolecular structure linked by a [Co2O2] unit due to the different coordination environments of the central metals. Three inorganic–organic hybrid POVs as heterogeneous catalysts are active in the selective oxidation of sulfides to produce sulfoxides or sulfones with high conversion and high selectivity (up to 99.5% for sulfoxides and 98.5% for sulfones respectively catalyzed by 1). Complex 1 is also used as catalyst in the oxidative CEES (2-chloroethyl ethyl sulfide, a sulfur mustard simulant) abatement with high activity and selectivity toward the corresponding sulfoxide. Moreover, complex 1 can be reused at least three times in sulfoxidation reactions without losing its activity.

A sulfur-decorated perylene derivative, 1-propanethiol-N,N′-dicyclohexyl perylene-3,4,9,10 tetracarboxylic diimide (PTPDI), was synthesized and fully characterized by 1H NMR, 13C NMR, FTIR, HRMS, UV–vis absorption, fluorescence, fluorescence lifetime, fluorescence quantum yield, cyclic voltammetry, and thermogravimetric techniques. The optical, fluorescence, and scanning electron microscopies were employed to study its self-assembly process. The photophysical properties were affected strongly by modifying the propanethiol unit linking to the perylene core. Furthermore, the chromophore showed two irreversible oxidations and two quasi-reversible reductions in dichloromethane at modest potential. The optical properties of PTPDI in various conditions and complementary density functional theory calculations were reported. Due to steric hindrance of the bulky n-propyl mercaptan substituent, PTPDI molecules are arranged in slipped face-to-face fashion to form J-aggregates. Thus, the intermolecular π–π actions of the molecule are weak, causing its high luminescence efficiency. In the meantime, the space between perylene cores is very short (3.45 Å), which is favorable for the hopping transportation of charge carrier from one molecule to an adjacent one. PTPDI could be a candidate material for acquiring a well-defined organic nanostructure with excellent charge-transporting and light-emitting capabilities.

A highly efficient and reusable catalyst QA-HPMV was successfully prepared by the reaction of quinoline-2-formic acid (QA) with molybdovanadophosphoric heteropolyacid (H4PMo11VO40, HPMV) for the nitration of benzene. The physical and chemical properties of the sample was characterized by X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis and thermogravimetric analysis (TG). The characterization results showed that the formed QA-HPMV retained the Keggin structure of HPMV. As a catalyst for benzene nitration, QA-HPMV showed good catalytic performance and the yield of nitrobenzene was 82.5% under the optimized reaction conditions. As a heterogeneous catalyst, QA-HPMV can be easily recycled from the reaction medium by filtering and remained highly catalytic performance even after five runs of recycling.

Two novel organic–inorganic hybrid polyoxovanadates, i.e., [Ni(1-mIM)4(H2O)2][Ni(H2O)5]2V10O28·5.5H2O (compound 1) and [V(O)(1-vIM)4]2V4O12·H2O (compound 2) (1-mIM = 1-methylimidazole; 1-vIM = 1-vinylimidazole) were synthesized under routine conditions. The two polyoxovanadate hybrids were further unequivocally characterized by the usual physicochemical techniques such as single crystal X-ray diffraction (SCXRD), Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), thermogravimetric (TG) analyses and elemental analyses. The SCXRD analyses demonstrated that the three Ni2+ atoms of compound 1 presented distorted octahedral geometry; one of the three Ni2+ atoms coordinated with four 1-mIM molecules and two coordinated water molecules, thereby exhibiting a [NiN4O2] binding set. Furthermore, the other two Ni2+ atoms were coordinated with five water molecules and one decavanadate polyanion, presenting an [NiO6] coordination environment. The structure of 2 exhibited a central [V4O12]4− unit attached to the opposite sides of two [V(O)(1-vIM)4]2 groups, in which the V center displayed distorted octahedral configuration. More importantly, the two organic–inorganic hybrid polyoxovanadates were further studied using the Knoevenagel condensation reaction, and they were found to display efficient heterogeneous catalytic activities (yield up to 99%). The catalytic performance of compound 1 did not decrease even after three runs of catalytic cycling.

By virtue of their structural periodicity, tunability, high porosity and rich functionality, metal–organic frameworks (MOFs) are of great interest in catalysis. However, MOF crystals are fragile and difficult to use as robust adsorbents or catalysts without processing into shapes. Precise control of particle size and catalytic sites for MOFs during the shaping procedures is also highly desired yet hard to realize. A versatile size control method for lanthanide MOFs, especially our newly designed Ce-MOF (BIT-58), is developed. The coordination and steric effects of various modulators are investigated. With size reduction from micrometers to nanometers (∼25 μm to ∼30 nm), more accessible metal sites of BIT-58 are exposed (10 times increased acid site amount; 7 times higher mesopore volume) and the catalytic performance is significantly improved. Furthermore, nano-sized BIT-58 can be processed into films or coatings with excellent catalytic activity, which holds great potential in batch or continuous-flow catalytic processes.

Three pyrazole-3-carboxylic acid (H 2 pca) complexes, Cr(Hpca) 3 ·2H 2 O ( 1 ), Ni 2 (pca) 2 (H 2 O) 6 ·2H 2 O ( 2 ) and [Pb 2 (Hpca) 4 ] n ( 3 ), have been synthesized and fully characterized. The single crystal X-ray diffraction indicate that the mononuclear Cr(III) cation in complex 1 and binuclear Ni(II) cations in complex 2 are coordinated by pyrazole-3-carboxylic acid ligands and water molecules in a distorted octahedral geometry and the binuclear Pb(II) cations in complex 3 presents a distorted seven-coordinated {PbN2O5} pentagonal-bipyramid geometry. Notably, these complexes as effective heterogeneous catalysts show efficient catalytic activities for Knoevenagel condensation (yield up to 97%) and the catalyst can be recycled without losing activity.

Two transition metal (Cu and Pd)-catalyzed C-S, C-N, and C-C bond cross-coupling reactions for the preparation of N-fused benzo[4,5]imidazo[2,1-b]thiazole derivatives were developed. A variety of 3-substituted and 2,3-disubstituted benzo[4,5]imidazo[2,1-b]thiazoles were efficiently and conveniently synthesized from the coupling reaction via trans-1,2-diiodoalkenes, 1H-benzo[d]imidazole-2-thiols, and halobenzenes in moderate to excellent yields.

A novel banana-shaped molecule using 2,8-Dimethyl-6H,12H-5,11-methanodibenzo [b,f] [1,5]diazocine (Tr&ouml, ger&rsquo, s base) as bent-core was synthesized via double Carbon-Carbon cross-coupling reaction. The double Sonogashira cross-coupling reaction was optimized by using Pd(PPh3)2Cl2 as catalyst, CuI as cocatalyst and diisopropylamine as base in place of triethylamine. The structure of this compound was confirmed by 1H-NMR, 13C-NMR, Fourier transform infrared (FT-IR) spectroscopy and mass spectrometry.

Reutilization of carbon dioxide (CO2) and destruction of chemical warfare agents (CWAs) at ambient conditions are deemed as two of the crucial challenges to steer toward a more sustainable future because they can cause great hazard to human beings and environment. Design of stable, selective and powerful catalysts for multi-functional catalysis is highly desirable yet largely unmet. In this work, a series of novel decavanadate-based transition metal clusters (POVs-TM, compounds 1–5) have been reported. Compounds 1–5 possess decavanadate-centered structures in which one decavanadate cluster bridged two bridged or free transition metal units. Decavanadate unit, serving as redox center can construct bifunctional catalysis platform with transition metal. Thus-obtained clusters can serve as powerful bifunctional catalysts in both cycloaddition of CO2 and degradation of sulfur mustard simulant. Specially, compound 1 presented high performance (conv. up to 99.4 %, sele. up to 99.5 %) in chemical fixation of CO2 into valuable cyclic carbonates with simulated flue gas as the gas resource. Besides, compound 3 performed superior efficiency (conv. 98.9 %, sele. 98.7 %) than other catalysts in the degradation of sulfur mustard simulant under ambient conditions. These dual-function validated POVs-TM clusters hold much promise in the exploration of novel catalysts for applications like continuous catalytic or flow bed reactions.

Two ionic organic–inorganic hybrid compounds, [CuII(C2N2H8)2]4[CuII(C2N2H8)2(H2O)2]2[PNb12O40VVVIVO2]·(OH)2·11H2O (1) and [CoIII(C2N2H8)3]2[CoIII(C2N2H8)2(H2O)2]0.5[H2.5PNb12O40 VVVIVO2]·20H2O (2), based on P-centered dicapped polyoxoniobates and organometallic cations were isolated and structurally characterized by routine techniques. The trivalent cobalt complex-containing compound exhibits a looser arrangement compared with its divalent copper complex-containing counterpart, with a space volume of 34.9% for the former and 17.0% for the latter. The two compounds were proved to be effective in facilitating the oxidation of benzyl-alkanes to ketone products in a heterogeneous manner, evidencing the feasiblity of the strategy of self-immobilization of catalytically active, readily soluble PNb12O40(VO)2 species in crystalline solids.

Two cobalt(ii) compounds, namely, {[Co(HL)(bpy)(H2O)2]·DMF}n (1), and {[Co(HL)(bpe)]·0.5bpe}n (2) (H3L = 1,3-bis(2-carboxylphenoxy)benzoic acid, bpy = 4,4'-bipyridine, bpe = 4,4'-vinylenedipyridine), have been synthesized using cobalt(ii) transition metal salt with phenolic carboxylic acid and different N-donor ligands. The compounds were fully characterized by elemental analysis, infrared spectroscopy (IR), single crystal X-ray diffraction analysis, and thermogravimetric analysis (TGA). Both compounds exhibit 2-D (4,4)-sql networks but with a wavelike and a double layered arrangement, respectively. Remarkably, these two compounds not only exhibit field-induced single-ion relaxation magnetization but also exceptional catalytic activities of benzylic C-H oxidation (conv. 90.3-99%; sele. 98.1-99%).

In this study, two simple Schiff base copper complexes [Cu(H2O)2(HL)]·2H2O (Complex 1) (H3L = 2-OH-4-(OH)-C6H2CH=NCH2CO2H) and [Cu(py)2(HL)] (Complex 2) (Py = pyridine) were initially achieved and authenticated by single-crystal X-ray structure analyses (SXRD), powder X-ray diffraction analyses (PXRD), FT-IR spectroscopy, and elemental analyses. The SXRD reveals that the Cu2+ center in Complex 1 exhibited a distorted square pyramidal geometry, which is constructed based on phenolate oxygen, water molecules, carboxylate oxygen, and imine nitrogen from a deprotonated H3L ligand in an NO4 fashion. The Cu2+ atom in Complex 2 had distorted square pyramidal geometry, and was coordinated with two pyridine molecules and one Gly-Schiff base ligand, exhibiting an N3O2 binding set. Additionally, the free water molecules in Complex 1 linked independent copper complexes by intermolecular hydrogen bond to form a 2D framework. However, the one-dimensional chain supramolecular structure of Complex 2 was formed by the intermolecular O–H…O hydrogen bonds. The oxygen reduction performance of the two complexes was analyzed by cyclic voltammetry (CV) and the rotating disk electrode (RDE) method. Both complexes could catalyze the conversion of oxygen to water through a predominant four-electron pathway, and the Cu–NxOy moieties might be the functional moieties for the catalytic activity. The catalytic pathways and underlying mechanisms are also discussed in detail, from which the structure–activity relationship of the complexes was obtained.

Reaction of two related rigid terpyridine ligands, 4′-(4-cyanophenyl)-4,2′:6′,4-terpyridine (L1) and its derivative, 4′-(4-carboxyphenyl)-4,2′:6′,4-terpyridine (L2), with transition metal ions (Co2+ or Cu2+/Cu+), afforded four novel coordination compounds: Co(L1)Cl2 (1), Co3(L1)3Cl6 (2), CuI9(L1)4.5(CN)9 (3), and [CuII3(L2)6(H2O)6]·4H2O (4). Crystal structure analysis reveals that 1 is comprised of single-stranded 21 helical chains, and weak interactions involving C–H···Cl weak hydrogen bonding and π–π stacking interactions exist in the structure. The structure of 2 is comprised of 32 helices, which is compared with the structure of compound 1. 3 shows a three-dimensional (3D) 4-fold interpenetration structure. 4 exhibits a one-dimensional gridlike belt structure, which further builds 3D supramolecular architecture via π–π stacking interactions. These novel coordination compounds show exceptional catalytic activity for the oxidation of benzylic C–H bonds. Notably, compound 4 shows the best catalytic prope...

Three novel inorganic–organic hybrid copper vanadates α-[Cu(mIM)4]V2O6 (1), β-[Cu(mIM)4]V2O6 (2), and [Cu(mIM)2)](VO3)2 (3) (mIM = 1-methylimidazole) have been synthesized by rationally controlling of the hydrothermal conditions and fully characterized by single-crystal XRD, powder XRD, elemental analyses, TGA, and FT-IR spectroscopy. Interestingly, compounds 1 and 2 were isolated as geometric isomers by tuning the solvothermal reaction temperature. Because of the different coordination modes between the tetradentate [V4O12]4– and [Cu(mIM)4]2+ subunits, the supramolecular structures of the two isomers show a 3D framework with an interpenetrating diamond topology for 1 and a 2D network for 2, respectively. Compound 3 was obtained by tuning the reaction temperature and the ratio of mIM/H2O, which showed interesting left- and right-handed helixes with an identical pitch of ca. 5.388 A in its 2D network structure. As heterogeneous catalysts, compounds 1–3 exhibit excellent catalytic performance in the oxidati...

By the combination of Pd-complexes and [V10O28]6-, three Pd-decavanadate compounds [Pd(NH3)4]3[V10O28]·8H2O (1), [Pd(deta)(H2O)]2(NH4)2[V10O28]·2H2O (2) (deta = diethylenetriamine) and [Pd(dpa)2](Hdpa)2(Et3NH)2[V10O28]·2H2O (3) (dpa = 2,2'-dipyridylamine) have been successfully synthesized and thoroughly characterized using single X-ray diffraction (SXRD), powder X-ray diffraction (PXRD), infrared spectroscopy (FT-IR) and elemental analyses (EA). Interestingly, in the three compounds, the molar ratios of Pd to decavanadate vary from 3 : 1 to 1 : 1 by changing N-ligands. The three Pd-decavanadates as heterogeneous catalysts are active in the aerobic oxidation of benzylic hydrocarbons under solvent-free conditions without adding any additives and co-catalysts. Moreover, compound 1 can be reused three times without losing its activity.

Binary Pd-polyoxometalates (Pd(dpa)2)3- (PW12O40)2·12 DMSO (2), (Pd(dpa)2)3(PMo12O40)2·12 DMSO· 2H 2O (3), and (Pd(dpa)(DMSO)2)2(HPMo10V2O40)·4 DMSO (4) were synthesized by reaction of (Pd(dpa)(OAc)2)· 2H 2 O( 1; dpa = 2,2'-dipyridylamine) with three Keggin-type polyoxometa- lates and fully characterized by single-crystal and powder XRD analyses, IR spectroscopy, and elemental analyses. The synthesis is facile and straightforward, and the complicated ligand-modification procedure often used in the traditional charge-transfer method can be omitted. In 2-4, Pd com- plexes and polyoxometalate anions are coupled through electrostatic interaction. Compound 4 is more active than the other three compounds in the selective aerobic oxida- tion of alcohols at ambient pressure. Interestingly, dur- ing catalytic recycling of compound 4, unprecedented ternary Pd-V-polyoxometalate (Pd(dpa)2{VO(DMSO)5}2)- (PMo12O40)2·4 DMSO (5), which was captured and character- ized by single-crystal XRD, proved to be the true active spe- cies and showed high catalytic activity for the selective aero- bic oxidation of aromatic alcohols (98.1-99.8 % conversion, 91.5-99.1 % selectivity). Moreover, on the basis of control ex- periments and EPR and UV/Vis spectra, a plausible reaction mechanism for the oxidation of alcohols catalyzed by 5 was proposed.

HKUST-1@Fe3O4 chemically bonded core-shell nanoparticles have been prepared by growing HKUST-1 thin layers joined by carboxyl groups onto Fe3O4 nanospheres. These magnetic core-shell MOF nanostructures show exceptional catalytic activity for the oxidation of benzylic C-H bonds and they can be recovered by magnetic separation and reused without losing any activity.

The applications of metal-organic frameworks (MOFs) toward industrial separation, catalysis, sensing, and some sophisticated devices are drastically affected by their intrinsic fragility and poor processability. Unlike organic polymers, MOF crystals are insoluble in any solvents and are usually not thermoplastic, which means traditional solvent- or melting-based processing techniques are not applicable for MOFs. Herein, a continuous phase transformation processing strategy is proposed for fabricating and shaping MOFs into processable fluids, shaped bodies, and even MOF foams that are capable of reversible transformation among these states. Based on this strategy, a cup-shaped Cu-MOF composite and hierarchically porous MOF foam were developed for highly efficient catalytic C-H oxidation (conv. 76% and sele. 93% for cup-shaped Cu-MOF composite and conv. 92% and sele. 97% for porous foam) with ease of recycling and dramatically improved kinetics. Furthermore, various MOF-based foams with low densities (0.1 g cm(-3)) and high MOF loadings (up to 80 wt %) were obtained via this protocol. Imparted with hierarchically porous structures and fully accessible MOFs uniformly distributed, these foams presented low energy penalty (pressure drop20 Pa, at 500 mL min(-1)) and showed potential applications as efficient membrane reactors.

Metal-organic frameworks (MOFs), as a class of microporous materials with well-defined channels and rich functionalities, hold great promise for various applications. Yet the formation and crystallization processes of various MOFs with distinct topology, connectivity, and properties remain largely unclear, and the control of such processes is rather challenging. Starting from a 0D Cu coordination polyhedron, MOP-1, we successfully unfolded it to give a new 1D-MOF by a single-crystal-to-single-crystal (SCSC) transformation process at room temperature as confirmed by SXRD. We also monitored the continuous transformation states by FTIR and PXRD. Cu MOFs with 2D and 3D networks were also obtained from this 1D-MOF by SCSC transformations. Furthermore, Cu MOFs with 0D, 1D, and 3D networks, MOP-1, 1D-MOF, and HKUST-1, show unique performances in the kinetics of the C-H bond catalytic oxidation reaction.

Four alkoxohexavanadate-based Pd-POVs [Pd(dpa)(acac)]2[V6O13(OMe)6] (1), [Pd(dpa)(acac)]2[V6O11(OMe)8] (2), [Pd(dpa)(acac)]2[V6O11(OMe)8]·H2O (3), and [Pd(DMAP)2(acac)]2[V6O11(OMe)8]·H2O (4) (POV = polyoxovanadate; dpa = 2,2'-dipyridine amine; DMAP = 4-dimethylaminopyridine; acac = acetylacetone anion) have been synthesized and fully characterized by single crystal X-ray diffraction and powder X-ray diffraction analyses, Fourier transform infrared spectroscopy, element analyses, and X-ray photoelectron spectroscopy. In 1-4, Pd complexes and hexavanadate anions are assembled through electrostatic interactions. Interestingly, the [V6O11(OMe)8](2-) cores in 2 and 3 are a pair of isomers that can be isolated by controlling crystallization temperature. Moreover, to the best of our knowledge, the {V6} core in 3 represents a new octamethoxyhexavanadates cluster. It is notable that compounds 1-4 exhibit excellent heterogeneous catalytic performance in the oxidation of benzyl-alkanes with t-butylhydroperoxide as oxidant. Among them, the catalytic activity of 1 (conv. and selec. up to 99%, respectively) outperforms others and can be reused without losing its activity.

Three zinc-trimesic acid (Zn-BTC) MOFs, BIT-101, BIT-102 and BIT-103, have been synthesized via a structure-directing strategy. Interestingly, BIT-102 and -103 exhibit extraordinary catalytic performance (up to Conv. 100% and Sele. 95.2%) in the cycloaddition of CO2 under solvent- and halogen-free conditions without any additives or co-catalysts.

Cluster cat: Three new imidazole-functionalized neutral hexanuclear vanadium clusters have been prepared, one of which shows exceptional catalytic activity in the selective aerobic oxidation of alcohols (see scheme). Furthermore, these new polyoxovanadium clusters can be readily recycled and reused with unchanged catalytic activity. A plausible catalytic cycle is also proposed.