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Herein, we report a novel palladium (Pd)-catalyzed asymmetric domino Heck/carbocyclization/Suzuki reaction of N-(2-bromoaryl)-2-naphthylacrylamides. The reaction involves a novel and enantioselecti...

Rhodium-catalyzed asymmetric desymmetrization Pauson-Khand reaction of C4-alkynyl-tethered cyclohexadienones has been developed as a novel strategy for access to fused 6-5-5 tricycles bearing three consecutive stereogenic centers. An array of chiral tricyclo[6.2.1.04,11]undecenes have been synthesized in high yields and enantioselectivities in a single step under mild conditions. This strategy employs readily accessible internal-olefin-containing 1,6-enynes, providing a potentially powerful tool for constructing chiral polycyclic scaffolds of complex molecules containing cyclopentenones and cyclohexenones.

Hydroaminocarbonylation of alkenes is one of the most promising yet challenging methods for the synthesis of amides. Herein, we reported the development of a novel and effective Pd-catalyzed Markovnikov hydroaminocarbonylation of 1,1-disubstituted or 1,1,2-trisubstituted alkenes with aniline hydrochloride salts to afford amides bearing an α quaternary carbon. The reaction makes use of readily available starting materials, tolerates a wide range of functional groups, and provides a facile and straightforward approach to a diverse array of amides bearing an α quaternary carbon. Mechanistic investigations suggested that the reaction proceeded through a palladium hydride pathway. The hydropalladation and CO insertion are reversible, and the aminolysis is probably the rate-limiting step.

An amazing and stable carbonized octahedral frame material Cu-PC@OFM was synthesized and characterized through HRTEM, SEM, XRD, XPS, and Raman spectroscopy and nitrogen adsorption/desorption analysis. In particular, the carbon matrix carrier loaded with nano-copper not only maintains the original structure, but also the nano copper particles generated in situ significantly improve the catalytic performance and stability. It was disclosed that the copper-based catalyst material Cu-PC@OFM showed high catalytic activity in the borrowing hydrogen reaction and the synthesis of 1-benzyl-2-aryl-1H-benzo[d]imidazole derivatives with high yields in water. This copper catalytic system provided a much greener and efficient catalyst for the synthesis of functionalized amines and 1-benzyl-2-aryl-1H-benzo[d]imidazoles with good recovery performance in water, which was the first example for the Cu-PC@OFM material-catalyzed synthesis of 1-benzyl-2-aryl-1H-benzo[d]imidazoles. In addition, a plausible reaction mechanism was proposed through some condition control experiments, deuterium labeling experiments and separation of intermediates experiments.

An efficient strategy for the construction of fused imidazole derivatives through a palladium-catalyzed isocyanide insertion reaction has been accomplished. The methodology provides an operationally simple and versatile route for the synthesis of indeno[1,2-d]imidazole and imidazo[1,2-a]indole skeletons which are rarely reported. The key features of the protocol are construction of sequential C-C/C-C/C-N bonds via C(sp2)-H functionalization of imidazole at the C2- and C4-position, respectively. The compounds can be synthesized with diverse scaffolds, easily accessible starting materials, and moderate to good yields.

The diphosphine ligand N,N-bis(diphenylphosphanylmethyl)-aniline (bdppma) and PdCl2 afforded a Suzuki–Miyaura catalyst [(bdppma­)PdCl2] that was highly efficient at an ultralow catalyst loading (0.001 mol%) in 20:1 H2O–EtOH. This low catalyst loading in an aqueous solvent system permitted simple product separation by direct filtration without the need for chromatography. The ligand bdppma imparted surprisingly better reactivity than that achieved with other bidentate diphosphine ligands, but the catalytic system had a slightly narrower substrate scope than some similar Pd catalysts reported previously.

Hydrogen will be an important energy vector of the future, and improved efficiency in electrohydrolysis will accelerate this transition. In a fundamental study, we have prepared Co(II) and Ni(II) complexes of a new PNN type ligand N-((diphenylphosphanyl)methyl)-2-amino-1,10-phenanthroline (dppmaphen) incorporating the photoactive 1,10-phenanthroline group and the strongly coordinating diphenylphosphine to obtain photoelectrochemical (PEC) catalysts [Co(dppmaphen)2(NO3)2] (1) and [Ni(dppmaphen)2Cl]Cl (2) which catalyzed the hydrogen evolution reaction (HER) in alkaline media (1 M KOH). Overpotentials (η10) of 430 (1) and 364 mV (2) could be reduced to 345 (1) and 284 mV (2) under Xe light irradiation. This irradiation generated photocurrent responses of 528 (1) and 357 uA/cm2 (2). Density function theory (DFT) calculation on the frontier orbitals of 1 and 2 were useful in understanding these differences in catalytic performance.

Three fluorescent coordination polymers (CPs) including [Zn(ppvppa)(5-NO2-1,3-BDC)(H2O)] (1), [Cd(ppvppa)2(2,5-FDC)]·1.5H2O (2), and [Ni(ppvppa)(5-NO2-1,3-BDC)(H2O)]·0.5MeCN (3) (ppvppa = dipyridin...

A quaternary compound Bi3O2S2Cl, which consists of novel [BiS2Cl]2-layers, is reported. It adopts a layered structure of the space group I4/mmm (No. 139) with lattice parameters: a = 3.927(1) {\AA}, c = 21.720(5) {\AA}. In this compound, bismuth and chlorine atoms form an infinite planar layer, which is unique among the bismuth halides. Superconductivity is observed in both polycrystals and single crystals, and is significantly enhanced in the samples prepared with less sulfur or at higher temperatures. By tuning the content of sulfur, Bi3O2S2Cl can be converted from a semiconductor into a superconductor. The superconducting critical temperature ranges from 2.6 K to 3.5 K. Our discovery of the [BiS2Cl]2- layer opens another door in searching for the bismuth compounds with novel physical properties., Comment: 15 pages

In this study, we aim to explore the anti-tumor effect of liraglutide (Lira), an anti-diabetic medicine, on pancreatic cancer cell PANC-1 co-cultured with or without pancreatic stellate cells (PSCs). The chemical count kit-8 and Annexin V-FITC apoptosis detection were conducted to investigate the effect of Lira on cell viability and proliferation of PANC-1 with or without PSCs co-culture. Then, the wound healing and transwell experiments were performed to explore the influence of Lira on PANC-1 cells' migration and invasion capabilities. To identify the potential action mechanism of Lira on PANC-1, the expression of E-cadherin and N-cadherin and the intracellular calcium content in PANC-1, after Lira administration, were detected. The results indicated that Lira in 100 and 1,000 nmol/L, effectively decreased the cell viability and dose-dependently promoted cell apoptosis of PANC-1 co-cultured with or without PSCs. Lira significantly reduced the migration and invasion of PANC-1 and also reduced the inducing effect of PSCs to PANC-1. Lira effectively induced the expression of E-cadherin and suppressed the expression of N-cadherin with a dose-dependent manner. Otherwise, Lira significantly reduced the abnormal high content of calcium in PANC-1 and also weakened the elevation of calcium in PANC-1 induced by cell-cell interaction. The current study firstly indicated that Lira suppressed the cell proliferation, migration and invasion of PANC-1 with or without PSCs co-culture. This effect was partially due to the calcium modulation of Lira and its influence on Ca2+-binding proteins, such as E-cadherin and N-cadherin.

Asymmetric hydroxycarbonylation is one of the most fundamental yet challenging methods for the synthesis of carboxylic acids. Herein, we reported the development of a palladium-catalyzed highly enantioselective Markovnikov hydroxycarbonylation of vinyl arenes with CO and water. A monodentate phosphoramidite ligand L6 plays vital role in the reaction. The reaction tolerates a range of functional groups, and provides a facile and atom-economical approach to an array of 2-arylpropanoic acids including several commonly used non-steroidal anti-inflammatory drugs. The catalytic system has also enabled an asymmetric Markovnikov hydroalkoxycarbonylation of vinyl arenes with alcohols to afford 2-arylpropanates. Mechanistic investigations suggested that the hydropalladation is irreversible and is the regio- and enantiodetermining step, while hydrolysis/alcoholysis is probably the rate-limiting step.

Reactions of Zn(OAc)2·2H2O with N1,N4-bis(5-fluoropyridin-3-yl)succinamide (bfps) and 1,2,3-benzenetricarboxylic acid (1,2,3-H3BTC) or 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC) under hydrothermal conditions produce two Zn(II)-based coordination polymers (CPs), {[Zn3(bfps)(1,2,3-BTC)2(H2O)6]·4H2O}n (1·4H2O) and {[Zn(bfps)(1,3,5-HBTC)]·H2O}n (2·H2O). Both compounds show two-dimensional layer structures derived from interconnecting dinuclear [Zn2(1,2,3-BTC)2(H2O)2] units through the bfps bridges and the [Zn(H2O)4] species (1·4H2O) or interlinking dinuclear [Zn2(1,3,5-HBTC)2] units via pairs of bfps bridges and pairs of 1,3,5-HBTC dianions (2·H2O). They display high absorptive capacities toward Orange IV (OIV) in water, i.e., 718 mg·g–1 (1·4H2O) and 794 mg·g–1 (2·H2O), respectively. The resulting CP-OIV composites with the chemical formulas of 1·2.0OIV (3) and 2·1.1OIV·2.5H2O (4) exhibit enhanced photocurrent responses in relation to those of the two precursors.

A novel and efficient strategy for the synthesis of 1,6-dihydropyridazines via copper-promoted 6- endo-trig cyclization of readily available β,γ-unsaturated hydrazones have been developed. A series of 1,6-dihydropyridazines have been synthesized by this method with good yields, high functional group tolerance, and remarkable regioselectivity under mild conditions. Importantly, the 1,6-dihydropyridazines can be efficiently converted to biologically important pyridazines in the presence of NaOH.

A novel and efficient copper-catalyzed tandem oxidative cyclization/1,2-amino migration of readily available enamino esters for the synthesis of substituted pyrroles has been developed. In this reaction, one C–N bond was cleaved, and two new C–N bonds and one C(sp2)–C(sp2) bond were constructed in one pot. This catalytic system has the obvious advantages of mild reaction conditions and the use of oxygen as the oxidant. The reaction tolerates a wide range of functional groups and is a reliable method for the straightforward synthesis of valuable aminomethyl-substituted pyrroles in good yields.

An efficient one-pot synthesis of quinazolin-4(3H)-ones, benzoimidazo[2,1-b]quinazolin-12(6H)-ones and imidazo[2,1-b]quinazolin-5(1H)-ones via a palladium-catalyzed domino process has been developed. The Pd-catalyzed reactions of 2-azidobenzamides 1 with isocyanides 2 produced quinazolin-4(3H)-ones 4 at room temperature by a domino Pd-catalyzed cross-coupling/carbodiimide-mediated cyclization. However, as 2-azido-N-(2-bromophenyl)benzamides 1 were used under heating condition in the presence of Cs2CO3, the benzoimidazo[2,1-b]quinazolin-12(6H)-ones 5 were directly obtained by twice Pd-catalyzed domino cyclization. A domino reogioselective 5-exo-dig intramolecular cyclization reaction of alkynyl-containing azides 6 with isocyanides 2 generated imidazo[2,1-b]quinazolin-5(1H)-ones 9 in 74–93% yields in the presence of catalyst Pd(PPh3)4 and K2CO3.

Anaerobic ammonium oxidation (anammox) process exhibits advantages in treating high-ammonium livestock wastewater, while the anammox bacteria is vulnerable to heavy metal and antibiotics. Arsenic and sulfonamides extensively existed in livestock wastewater; unfortunately, their effects on the anammox process have not yet been investigated. This work comprehensively evaluated the single and joint effects of As(III) and sulfamethoxazole (SMX) on the anammox process and revealed the related inhibitory mechanism. Anammox had extraordinary resistance to As(III) stress (0–50 mg L−1), while nitrogen removal sharply deteriorated under the stress from 50 mg L−1 As(III) and 3 mg L−1 SMX. Exogenous As(III) damaged the protection of extracellular polymeric substance (EPS) and aggravated the inhibition of SMX. As(III) had direct toxic effects on anammox bacteria, while enhanced denitrifying capacity was the reason for inhibition of anammox by SMX. Moreover, the host arsenic resistance genes were changed under SMX inhibition. The findings of this study enrich our knowledge of the anammox response to various pollutants, and provide the operational guidance for anammox process to treat wastewater containing antibiotic and heavy metal.

A novel palladium-catalyzed oxidative cyclopropanation of enamides and norbornenes has been developed. The reaction proceeded through palladium-catalyzed vinyl C–H bond activation of enamides followed by two migratory insertions, β-( N )H elimination and hydrolyzation cascade steps. The reaction tolerates a range of functional groups and provides an effective method for the synthesis of cyclopropane-fused norbornanes in good yields under mild conditions.

One palladium dichloride adduct of a phosphine-pyridine ligand N-diphenylphosphanyl-2-aminopyridine (L1) [(L1)PdCl2] (1) has been prepared and structurally characterized. Compound 1 can be used as an effective catalyst for the Suzuki-Miyaura cross-coupling reactions of unreactive aryl chlorides with aryl boronic acids, and worked much better than its mono- or bidentate phosphine ligands. The reactions with a wide scope of substrates proceeded to give desired products in good to excellent yields.

A green protocol for the synthesis of quinoxalines has been developed from catalytic oxidative cyclization of deoxybenzoins with 1,2-phenylenediamines in water. The optimal conditions are involved in the use of a water-soluble mononuclear copper(II) complex of a zwitterionic calix[4]arene [Cu(II)L(H 2 O)]I 2 ( 1 , H 4 L = [5,11,17,23–tetrakis (trimethylammonium)–25,26,27,28–tetrahydroxycalix[4]arene]) as a catalyst in alkali solution after refluxing for 15 h in O 2 . The target quinoxaline and its derivatives were obtained in good yields (up to 88%). The procedure described in this paper is simple, practical and environmentally benign.

An efficient catalytic system containing [RuCl2(η6-p-cymene)]2 and one P,N ligand, N-diphenylphosphino-2-aminopyridine (L1) was loaded in catalyzing the alkylation of ketones with primary alcohols for a diverse array of substrates. Other five P,N ligands based on pyridin-2-amine and pyrimidin-2-amine were also examined in this reaction to explore the influence of steric hindrance and electronic effects. Monitoring by 1H NMR and ESI-MS reveals a stable cationic L1-coordinated ruthenium hydride intermediate, identified as [Ru(η6-p-cymene)(κ2-L1)H]+. Organic intermediates consistent with a three-step dehydrogenation, alkylation and hydrogenation pathway were also observed. The final step in this reaction, the ruthenium-catalysed transfer hydrogenation reduction of α,β-unsaturated ketone with benzyl alcohol was performed separately.

Three photoluminescent zinc coordination polymers (CPs), {[Zn2(tpeb)2(2,5-tdc)(2,5-Htdc)2]·2H2O}n (1), {[Zn2(tpeb)2(1,4-ndc)(1,4-Hndc)2]·2.6H2O}n (2), and {[Zn2(tpeb)2(2,3-ndc)2]·H2O}n (3) (tpeb = 1,3,5-tri-4-pyridyl-1,2-ethenylbenzene, 2,5-tdc = 2,5-thiophenedicarboxylic acid, 1,4-ndc = 1,4-naphthalenedicarboxylic acid, and 2,3-ndc = 2,3-naphthalenedicarboxylic acid) were prepared from reactions of Zn(NO3)2·6H2O with tpeb and 2,5-H2tdc, 1,4-H2ndc, or 2,3-H2ndc under solvothermal conditions. Compound 1 has a two-dimensional (2D) grid-like network formed from bridging 1D [Zn(tpeb)]n chains via 2,5-tdc dianions. 2 and 3 possess similar one-dimensional (1D) double-chain structures derived from bridging the [Zn(tpeb)]n chains via pairs of 1,4-ndc or 2,3-ndc ligands. The solid-state, visible emission by 1–3 was quenched by Cr3+, CrO42–, and Cr2O72– ions in water with detection limits by the most responsive complex 3 of 0.88 ppb for Cr3+ and 2.623 ppb for Cr2O72– (pH = 3) or 1.734 ppb for CrO42– (pH = 12). Thes...

Cobalt catalysts have evolved to be seen as versatile eco-compatible and economical catalysts in organic synthesis in recent years. Cobalt-catalyzed reactions are undoubtedly a classic in synthetic chemistry for the formation of carbon–carbon and carbon–heteroatom bonds. Another important aspect in this field is catalyst variants, such as low-valent and high-valent cobalt catalysts. This review summarizes the recent progress and synthetic utility of low-valent and high-valent cobalt catalysts towards C–H functionalization processes achieving C–C, C–O, C–N and C–B bond formation. Mechanistic insight is also discussed, with the goal of serving as a stepping stone for further development in this field. In addition, Csp3–H bond functionalization reactions provide many opportunities for novel synthesis approaches. 1 Introduction 2 Carbon–Carbon Bond Formation 2.1 Csp2–Csp3 Bond Formation 2.2 Csp2–Csp2 Bond Formation 3 Carbon–Nitrogen Bond Formation 4 Csp3–H Bond Functionalization 5 Carbon–Oxygen Bond Formation 6 Carbon–Boron Bond Formation 7 Conclusion

Solvothermal reactions of Cd(NO3)2·4H2O with 4-pyr-poly-2-ene (ppene) in the presence of benzene-1,2-dicarboxylic acid (1,2-H2BDC), benzene-1,3-dicarboxylic acid (1,3-H2BDC), benzene-1,4-dicarboxylic acid (1,4-H2BDC), benzene-1,3,5-tricarboxylic acid (1,3,5-H3BTC), or 4,4′-oxidibenzoic acid (4,4′-H2OBA) afforded five Cd(II) coordination polymers [Cd(ppene)(1,2-BDC)]n (1), [Cd(ppene)(1,3-BDC)]n (2), [{Cd(ppene)(1,4-BDC)}·MeCN]n (3) (Liu et al. Inorg. Chem. Commun. 2015, 58, 1−4), [{Cd(ppene)(1,3,5-HBTC)}·0.5(ppene)]n (4), and [Cd(ppene)(4,4′-OBA)]n (5), respectively. Upon UV light irradiation, 1, 3, and 4 can undergo a double [2 + 2] cycloaddition reaction to yield their corresponding photoproducts including [Cd2(4-tp-3-lad)(1,2-BDC)2]n (1a, 4-tp-3-lad = 2,3,5,6-tetra(pyridin-4-yl)bicyclo[2.2.0]hexane), [{Cd2(4-tp-3-lad)(1,4-BDC)2}·2MeCN]n (3a), and [{Cd2(4-tp-3-lad)(1,3,5-HBTC)2}·(ppene)]n (4a) in a single-crystal-to-single-crystal manner. Compounds 1, 2, 4, 5, 1a, 3a, and 4a have been structurally charac...

An efficient iron-catalyzed cyclization of ketoxime acetates with N,N-dimethylaniline for the synthesis of symmetrical pyridines has been developed. A methyl carbon on N,N-dimethylaniline acts as a source of one carbon synthons. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,3,5,6-tetrasubstituted symmetrical pyridines in good yields.

A new Cu-catalyzed efficient protocol is described for the transformation of oximes to the corresponding carbonate derivatives. Diisopropyl azodicarboxylate acted as a selective new precursor for the synthesis of oxime carbonates in high yields. The O-H bond cleavage and O-C bond formation occur in the presence of a copper catalyst providing a synthetically useful process, which tolerates a wide range of functional groups.

Glassy carbon (GC), a non-graphitizing carbon which combines glassy and ceramic properties with those of graphite, have been doped to superconductors. The KGC8 presents Tc around 7.98 K is about dozens of times larger than that of potassium doped GIC. The results demonstrate that doped glass carbons are good model materials for studying the mechanism of superconductivity in carbon-based materials. Furthermore, to our best knowledge, it is the first time to get the superconductor from the polymer precursor.

A copper(I)-catalyzed aerobic oxidative coupling of ketoxime acetates with simple pyridines for the synthesis of imidazo[1,2-a]pyridines has been developed. This reaction tolerates a wide range of functional groups and it affords a series of valuable imidazo[1,2-a]pyridines in high yields under mild conditions.

A novel and efficient iron-catalyzed cyclization of ketoxime carboxylates and N,N-dialkylanilines for the modular synthesis of diverse pyridines was developed. The reaction was initiated by Fe-catalyzed N-O bond cleavage of ketoxime carboxylates in the presence of tertiary anilines. The methylene carbon on N,N-dialkylanilines functioned as a source of one-carbon synthon in the reaction. The reaction used readily available starting materials, tolerated various functional groups, and afforded 2,4-disubstituted and 2,4,6-trisubstituted pyridines in good to high yields under mild conditions.

An efficient copper(I)-catalyzed oxidative tetrahydrofuranylation of oximes has been developed. This reaction shows good functional group tolerance and various substituted ketoximes and aldoximes coupled smoothly with THF to give the corresponding O-tetrahydrofuran-2-yl oxime ethers in high yields.

The investigation of heterometallic Mo(W)-M'-S clusters (M' = transition metals) has its genesis in the late 1970s with the identification of the nitrogenase iron-molybdenum cofactor (FeMoco) featuring a Mo-Fe-S double-cubane cluster core. This has led to the generation of a library of cluster skeletons subsequently used as building blocks for oligomers (OGs) and polymers, merging this field with the fascinating developments in supramolecular chemistry and coordination polymers (CPs). While resembling the general metal-ligand assembly to form CPs in one-pot, cluster-based OGs or CPs are conventionally prepared from Mo(W)-S synthons and Cu(i) salts in the presence of bridging ligands. This review summarizes the synthesis of Mo(W)-Cu-S cluster-supported OGs and CPs through a two-step strategy involving preformed clusters. This stepwise approach facilitates clean conversion, and is amenable to exquisite design protocols and yields products otherwise inaccessible via a direct one-pot method. We review the synthesis of OGs and CPs by cluster core upgrading, downgrading, ligand substitution, and cluster aggregation reactions, together with the optical and host-guest properties of the products. In doing so, we demonstrate the power and generality of this strategy for assembling these unique materials and offer clues on how to adapt this less practiced method to preparing extended molecular assemblies with potentially intriguing properties.

Anatase titanium dioxide quantum dots (QDs) are synthesized by using a mixture of two kinds of titanium precursors and simple hydrothermal method in aqueous solution without any template and organic solvent. The obtained product is assessed by X-ray diffraction (XRD), selected area electrondiffraction (SAED), Raman spectroscopy, transmission electron microscopy (TEM) and ultraviolet-visible diffuse reflectance analysis (UV-DRS). The results of XRD, SAED and Raman spectrum demonstrate that pure anatase TiO2 is produced. The TEM images reveal that TiO2 anatase QDs are almost sphere in shape and with a mean particle diameter of ~4 nm. The energy band gap value (Eg) is calculated to be ~3.79 eV. The synthesized TiO2 QDs present enhanced photocatalytic activity and stability for the photodegradation of organic dyes under UV light irradiation.

We report superconductivity in a new ternary molybdenum pnictide Rb2Mo3As3, synthesized via the solid state reaction method. Powder x-ray diffraction analysis reveals a hexagonal crystal structure with space group P 6 ¯ m 2 (No. 187), and the refined lattice parameters are a = 10.431(5) Å, c = 4.460(4) Å. SEM images show rod-like grains with good ductility, confirming a quasi-one-dimensional (Q1D) structure. Electrical resistivity and dc magnetic susceptibility characterizations exhibit superconductivity with an onset of T c = 10.5 K. The upper critical field of Rb2Mo3As3 is estimated to be 28.2T at zero temperature, providing an evidence of possible unconventional superconductivity. Our recent discovery of MoAs-based superconductors above 10 K provides a unique platform for the study of exotic superconductivity in 4d electron systems with Q1D crystal structures.

A robust ligand-free palladium-catalyzed cascade reaction for the synthesis of diversely substituted iminoisoindolinones has been developed. The cascade reaction involves isocyanide insertion into Ugi-3CR adducts, accompanied by unexpected hydroxylation and rearrangement.

We report the observation of local superconductivity induced at the point contact formed between a normal metal tip and WC -- a triple point topological semimetal with super hardness. Remarkably, the maximum critical temperature is up to near 12 K but insensitive to the tip's magnetism. The lateral dimensions of the superconducting puddles were evaluated and the temperature dependencies of superconducting gap and upper critical field were also obtained. These results put constraints on the explanation of the induced superconductivity and pave a pathway for exploring topological superconductivity., Comment: 7 pages, 6 figures

Here we report the discovery of the first ternary molybdenum pnictide based superconductor K2Mo3As3. Polycrystalline samples were synthesized by the conventional solid state reaction method. X-ray diffraction analysis reveals a quasi-one-dimensional hexagonal crystal structure with (Mo3As3)2- linear chains separated by K+ ions, similar as previously reported K2Cr3As3, with the space group of P-6m2 (No. 187) and the refined lattice parameters a = 10.145(5) {\AA} and c = 4.453(8) {\AA}. Electrical resistivity, magnetic susceptibility, and heat capacity measurements exhibit bulk superconductivity with the onset Tc at 10.4 K in K2Mo3As3 which is higher than the isostructural Cr-based superconductors. Being the same group VIB transition elements and with similar structural motifs, these Cr and Mo based superconductors may share some common underlying origins for the occurrence of superconductivity and need more investigations to uncover the electron pairing within a quasi-one-dimensional chain structure.

A water-soluble cationic mononuclear copper(II) complex [Cu(II) L (H 2 O)]I 2 ( 1 , H 4 L = 5,11,17,23–tetrakis(trimethylammonium)-25,26,27,28-tetrahydroxycalix[4]arene) was employed as a catalyst in the oxidation of benzyl alcohols to benzaldehydes in water. In the presence of TEMPO and H 2 O 2 , complex 1 exhibited good catalytic activity towards primary benzyl alcohols with a less catalyst loading (0.25 mol%) and a lower temperature (60 °C). The isolated yields of the aldehydes achieved 63–98% within 12 h.

Alpha-fetoprotein (AFP), a primary marker for many diseases including various cancers, is important in clinical tumor diagnosis and antenatal screening. Most immunoassays provide high sensitivity and accuracy for determining AFP, but they are expensive, often complex, time-consuming procedures. A simple and rapid point-of-care system that integrates Eu (III) chelate microparticles with lateral flow immunoassay (LFIA) has been developed to determine AFP in serum with an assay time of 15 min. The approach is based on a sandwich immunoassay performed on lateral flow test strips. A fluorescence strip reader was used to measure the fluorescence peak heights of the test line (HT) and the control line (HC); the HT/HC ratio was used for quantitation. The Eu (III) chelate microparticles-based LFIA assay exhibited a wide linear range (1.0-1000 IU mL(-1)) for AFP with a low limit of detection (0.1 IU mL(-1)) based on 5ul of serum. Satisfactory specificity and accuracy were demonstrated and the intra- and inter-assay coefficients of variation (CV) for AFP were both

In this study, the anti-corrosion properties of nickel-based coatings on the surface of copper alloy were investigated, and damages caused by corrosion on the copper surface were resolved. Researchers prepared nickel-based coatings by supersonic particles deposition, and tested the anti-corrosion properties of brass substrate and nickel-based coating by electrochemical technology and neutral salt spray. The results show that, the corrosion current of coating decreased 35 times than that of matrix. The successive and pyknotic oxide film on the surface of coating prevented reaction of corrosion further. When it reached 500 hours, the corrosion rate closed to 0. Nickel-based coatings prepared by supersonic particles deposition contribute to the increase of corrosion resistance significantly, which verifies that it is feasible to prepare outstanding corrosion resisting nickel-based coating by supersonic particles deposition.

Suzuki–Miyaura coupling reactions of arylboronic acids with aryl bromides were mediated by PdCl2 and bdppmapy (N,N-bis-(diphenylphosphanylmethyl)-2-aminopyridine) that both stabilizes and solubilizes the catalyst in predominantly ethanol as a solvent. Excellent yields for a wide variety of substrates were obtained under relatively mild conditions in this ‘green’ solvent.

The coordination polymers (CPs) [Zn2(tipm)(1,3-BDC)2] (1) and [Co2(tipm)(1,3-BDC)2]·0.5CH3CN (2·0.5CH3CN) were synthesized by the reactions of Zn(NO3)2 or Co(NO3)2 with tetrakis[4-(1-imidazolyl)phenyl]methane (tipm) and benzene-1,3-dicarboxylic acid (1,3-H2BDC) under solvothermal conditions. Compounds 1 and 2 are isostructural and possess complicated three-dimensional frameworks with the Schlafli symbol (4·72)(62·73·12)(4·62·73). Cobalt ions were incorporated into the Zn-based CP framework 1 during solvothermal crystallization to yield [Zn(2–2x)Co2x(tipm)(1,3-BDC)2]·bH2O (x = 2.4 %, b = 0 for 1a, x = 23 %, b = 1 for 2a·H2O). Doped CPs 1a and 2a·H2O exhibited greater catalytic photodegradation of the dye rhodamine B (RhB) than the undoped complexes 1 and 2 and many literature examples.

Apatite-type lanthanum silicates doped with Pr3+ at the La site, La10-xPrxSi6O27 (x = 0, 1, 2, 3, 4, 4.5), were synthesized via sol-gel process. Thermal behavior of the dried gel of La10-xPrxSi6O27 sample was studied using TG/DTA. X-ray diffraction, SEM and complex impedance analysis were used to investigate the microstructure and electrical properties of La10-xPrxSi6O27 ceramics. The XRD results indicated the maximum doping quantity of Pr3+ is x = 4.5. Lanthanum silicates doped with Pr3+ cations have a higher total conductivity than that of undoped lanthanum silicates. The enhanced total conductivity depends on the improved density of La10-xPrxSi6O27 (x = 0, 1, 2, 3, 4, 4.5). At 973K, the highest total conductivity is 1.36×10-3S.cm-1 for La9PrSi6O27 ceramic.

A novel palladium-catalyzed carbonylation of indoles with CO and aromatic boronic acids for the synthesis of indol-3-yl aryl ketones was developed. The reaction tolerates a wide range of functional groups and gives a variety of valuable indol-3-yl aryl ketones in high yields under mild conditions.

Three tantalum oxyfluoride compounds, [Fe(phen)3][Ta2OF10] (1), [Fe(phen)3][Ta2OF10]·2H2O (2), and [Ru(phen)3]2[Ta2OF10][TaF6]2 (3), were synthesized by a two-step hydrothermal method and their crystal structures were characterized by single-crystal X-ray diffraction. The unique characters of these compounds are the [M(phen)3]2+ cations. C–H···F interactions exist between cations and anions and O–H···F hydrogen bonds exist between the water molecules and anions. Photocurrent measurements reveal that compound 3 is the photoelectric responsive with the moderate current intensity.

We report the synthesis, crystal structure, superconductivity and physical property characterizations of the ternary equiatomic compound ScRuSi. Polycrystalline samples of ScRuSi were prepared by an arc-melting method. The as-prepared samples were identified as the orthorhombic Co2P-type o-ScRuSi by the powder X-ray diffraction analysis. Electrical resistivity measurement shows o-ScRuSi to be a metal which superconducts below a Tc of 3.1 K, and the upper critical field {\mu}0Hc2(0) is estimated to be 0.87 T. The magnetization and specific heat measurements confirm the bulk type-II superconductivity in o-ScRuSi, with the specific heat jump within the BCS weak coupling limit. o-ScRuSi is the first Co2P-type superconductor containing scandium. After annealing at 1273 K for a week, o-ScRuSi transforms into the hexagonal Fe2P-type h-ScRuSi, and the latter is a Pauli-paramagnetic metal with no superconductivity observed above 1.8 K.

A novel palladium-catalyzed regioselective oxidative carbonylation of tri-substituted alkenes with CO and alcohols for the synthesis of α,β-unsaturated esters has been developed. Experimental studies and DFT calculations suggested that the reaction proceeded through alkoxylation of the palladium(ii) catalyst, CO and C[double bond, length as m-dash]C double bond migratory insertion, β-(N)H elimination and tautomerization cascade steps. The reaction tolerates a wide range of groups and produces valuable aminomethylenemalonates in high yields.

We report the observation of an extremely large magnetoresistance (up to 15 000 000% at 1.8 K in a magnetic field of 9 T) in a simple chemical element, gray arsenic, in which the magnitude of the magnetoresistance increases as approximately the square of the magnetic field strength without any signs of saturation. The Hall-effect study confirms that gray arsenic is a nearly perfect ``compensated semimetal,'' with a small concentration of very mobile carriers, which lead to an extremely large magnetoresistance. The analysis of Shubnikov--de Haas oscillations reveals a nontrivial \ensuremath{\pi} Berry phase, a strong signature of Dirac fermions with three-dimensional dispersion. Furthermore, in the presence of parallel magnetic and electric fields, a weak antilocalization effect and a pronounced negative longitudinal magnetoresistance, which may be linked to novel topological states, are also observed. These findings which uncover the material's basis in gray arsenic not only open avenues in spintronics and magnetic sensor applications but also provide more platforms to study topological materials.

Reactions of NiCl2·6H2O or Ni(ClO4)2·6H2O with 2,2′-bipyridine (2,2′-bipy), or 2-bis(diphenylphosphino)ethane (dppe) or 1,4-bis(diphenylphosphino)butane (dppb) followed by addition of [Zn(Tab)4](PF6)2 (1) resulted in the formation of one trinuclear cationic complex [(2,2′-bipy)4Ni3(μ-Tab)4]Cl0.5(PF6)5.5 (2), one mononuclear cationic complex [Ni(Tab)2(dppe)](PF6)2 (3), and one dinuclear cationic complex [Ni2(dppb)(μ-Tab)2(Tab)2](PF6)2(ClO4)2 (4). Complexes 2–4 were characterized by elemental analysis, IR, UV–vis, 1H and 31P NMR, and single-crystal X-ray diffraction. In the [(2,2′-bipy)4Ni3(μ-Tab)4]6 + hexacation of 2, the central Ni(II) atom is connected to two [Ni(2,2′-bipy)2]2 + fragments by two pairs of μ-Tab ligands, forming a linear trinuclear cationic structure. The Ni(II) center of the dication of 3 is tetrahedrally coordinated by two S atoms from two Tab ligands and two P atoms of one dppe ligand. Complex 4 has a dimeric cationic structure in which two [(Tab)Ni]2 + species are linked by a pair of μ-Tab ligands and one dppb ligand. Complexes 2–4 displayed high catalytic activity toward the cross-coupling reactions of arylboronic acids and amines to produce N-arylated amines.