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The tail of imidazole regulated the assembly of fascinating 2D sql topology and 3D 2-fold interpenetrated lvt structure polyoxotungstate-based open frameworks with efficient visible-white-light-driven aerobic catalytic oxidation of sulfides.

A robust and porous Ti-MOF, LCU-402, shows permanent porosity for CO2, CH4, C2H2, C2H4, and C2H6 gas adsorption, and can smoothly convert CO2 into organic carbonate molecules by cycloaddition of epoxides with CO2 in simulated flue gas.

A facile one-step ball-milling strategy to prepare gram-scale Mg3Al-LDH-Nb6 has been demonstrated and the thus-obtained catalyst exhibited efficient selective catalytic activities in the synthesis of biologically active organic molecules in water.

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.

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.

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.

Four new mixed-valence manganese complexes, [Mn(II)Mn(III)2(S-L1)2(OAc)4]·2H2O(1), [Mn(II)Mn(III)2(R-L1)2(OAc)4]·2H2O (2), [Mn(II)Mn(III)2(2H2O)(S-L2)2(OAc)4] (3), [Mn(II)Mn(III)2(2H2O)(R-L2)2(OAc)4] (4) [H2L1 derived from (R)/(S)-2-amino-1-butanol and 2-hydroxy-5-chlorobenzaldehyde, H2L2 derived from (R)/(S)-2-amino-3-phenyl-1-propanol and 2-hydroxy-4-methoxybenzaldehyde], were synthesized and fully characterized by elemental analysis, IR spectroscopy and single crystal X-ray diffraction. Complexes 1–4 are mixed-valence trinuclear manganese compounds with six-coordinated. The linear MnIII–MnII–MnIII cores are triply bridged by acetate, phenolate and alkoxy groups. The vitro cytotoxicity test revealed that all complexes have substantial cytotoxic activity against three cancer cell lines (HepG2, MDA-MB-231 and A549). DNA-binding properties of 1–4 were investigated by UV–Vis, fluorescence spectroscopy, viscosity and thermal denaturation. All complexes bound to calf thymus DNA (CT-DNA) via an intercalative mode, and that derived from (S)-Schiff base ligands exhibited stronger interaction with DNA than (R)-isomers. Furthermore, the interactions of 1–4 with bovine serum albumins (BSA) in a static mode were also studied using absorption emission spectral techniques and molecular docking analysis. The chirality and structure of ligands showed to a large influence on the DNA/BSA binding ability and cytotoxicity of manganese complexes. The geometry optimization results are in agreement with experimental observations.

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 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%).

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.

Invited for the cover of this issue is the group of Changwen Hu at the Beijing Institute of Technology, China. The cover image shows the most recent developments in the synthesis and study of the gas-phase fragmentation of new polyoxopalladates.

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.

Seven polyoxopalladate compounds, [Pd(15)(SeO(3))(10)(μ(3)-O)(10)](10-), with Na(+) (1) and K(+) (2) as counterions, and Na(6)[M(II){Pd(12)(SeO(3))(8)(μ(4)-O)(8)}]·nH(2)O (M = Co (3), Zn (4), Ni (5), Cu (6), Mn (7); n = 7-9), have been prepared and characterized by SXRD, FT-IR, UV-vis, EA, TGA, and ESI-MS. These compounds comprise two distinct cluster configurations, {Pd(15)} and {M(II)Pd(12)}, which reveals the possibility of obtaining desired noble metal clusters with a certain nuclearity by using different cations as potential structural directing or template agents in synthesis. All compounds showed apparent absorptions in the visible light region, while 3 and 7 were found to show paramagnetic behavior typical of mononuclear Co(II) and Mn(II) complexes with zero-field splitting.