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Arsenic doping in silicides has been much less studied compared with phosphorus. In this study, superconductivity is successfully induced by As doping in Mo$_5$Si$_3$. The superconducting transition temperature ($T_c$) reaches 7.7 K, which is higher than those in previously known W$_5$Si$_3$-type superconductors. Mo$_5$Si$_2$As is a type-II BCS superconductor with upper and lower critical fields of 6.65 T and 22.4 mT, respectively. In addition, As atoms are found to selectively take the 8$h$ sites in Mo$_5$Si$_2$As. The emergence of superconductivity is possibly due to the shift of Fermi level as a consequence of As doping, as revealed by the specific heat measurements and first-principles calculations. Our work provides not only another example of As doping, but also a practical strategy to achieve superconductivity in silicides through Fermi level engineering., Comment: Supporting Information available at the corresponding DOI

Understanding the microbial and chemical diversities, as well as what affects these diversities, is important for modern manufacturing of traditional fermented foods. In this work, Chinese dark teas (CDTs) that are traditional microbial fermented beverages with relatively high sample diversity were collected. Microbial DNA amplicon sequencing and mass spectrometry-based untargeted metabolomics show that the CDT microbial β diversity, as well as the nonvolatile chemical α and β diversities, is determined by the primary impact factors of geography and manufacturing procedures, in particular, latitude and pile fermentation after blending. A large number of metabolites sharing between CDTs and fungi were discovered by Feature-based Molecular Networking (FBMN) on the Global Natural Products Social Molecular Networking (GNPS) web platform. These molecules, such as prenylated cyclic dipeptides and B-vitamins, are functionally important for nutrition, biofunctions, and flavor. Molecular networking has revealed patterns in metabolite profiles on a chemical family level in addition to individual structures.

Antibiotics are widely found in nitrogen-containing wastewater, which may affect the operation stability of anaerobic ammonium oxidation (anammox)-based biological treatment systems. Extracellular polymeric substances (EPSs) of anammox sludge play a pivotal role in combining with antibiotics; however, the exact role and how the structure of the leading component of EPSs (i.e., extracellular proteins) changes under antibiotic stress remain to be elucidated. Here, the interaction between sulfamethoxazole and the extracellular proteins of anammox sludge was investigated via multiple spectra and molecular simulation. Results showed that sulfamethoxazole statically quenched the fluorescent components of EPSs, and the quenching constant of the aromatic proteins was the largest, with a value of 1.73 × 10

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.

The methodology for the transformation of CO2 into high-value chemicals is the Holy Grail of sustainable chemistry [Carter Acc. Chem. Res. 2017, 50, 472−475]. Herein, we report the carboxylation of...

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.

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.

A one-pot novel strategy is described for the construction of various oxazolo[4,5-c]quinoline derivatives starting from the isocyano(triphenylphosphoranylidene)acetates, aldehydes, amines, and 2-azidobenzoic acids. The reactions generated the target products directly in moderate to good yields via a sequential Ugi/Wittig/aza-Wittig cyclization process. The salient features of the method are that all three groups of the multifunctional isocyanides were involved in the reaction with broad substituent scopes and mild reaction conditions, making the protocol a useful contribution to the synthesis of oxazolo[4,5-c]quinoline heterocycles.

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...

Reactions of the phosphanyl-gold(I) precursor [(AuCl)2(bdppmapy)] (1; bdppmapy = N,N-bis(diphenylphosphanylmethyl)-2-aminopyridine) with Na2S in a 1:1 or 1:2 molar ratio gave rise to one tetradecanuclear and one octanuclear Au(I) sulfido cluster, [Au14S6(bdppmapy)5]Cl2 (2) and [Au18S8(bdppmapy)6]Cl2 (3), respectively. The former displays a new structural framework in gold cluster chemistry. Compounds 2 and 3 showed strong green luminescence and were employed as excellent imaging probes to selectively light up the lysosomes of living cells. Their long-term tracking of lysosomes can be achieved for up to 36 h, while tracking with commercial Lyso-Tracker Red under the same conditions was limited to 3 h. Our work demonstrated the possibility of constructing novel gold(I) sulfido clusters supported by special P-N hybrid ligands and the potential application of these clusters as long-term selective trackers of lysosomes in bioimaging.

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

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.

The observation of a reversible chemical transformation corresponding to an external stimulus in the solid state is intriguing in the exploration of smart materials, which can potentially be applied in molecular machines, molecular switches, sensors, and data storage devices. The solid-state photodimerization reaction of 1,3-bis[2-(4-pyridyl)ethenyl]benzene (1,3-bpeb) in a one-dimensional coordination polymer {[Cd2(1,3-bpeb)2(4-FBA)4]·H2O}n (4-FBA = 4-fluorobenzoate) with 365 nm UV light afforded syn-tetrakis(4-pyridyl)-1,2,9,10-diethano[2.2]metacyclophane (syn-tpmcp) in quantitative yield via a single-crystal-to-single-crystal (SCSC) transformation. Upon irradiation with 254 nm UV light, an SCSC conversion from syn-tpmcp to 1,3-bpeb was also achieved in quantitative yield within the syn-tpmcp-supported coordination polymer {[Cd2(syn-tpmcp)(4-FBA)4]·H2O}n. In particular, accompanied by the reversible transformation between 1,3-bpeb and syn-tpmcp, the coordination chain exhibits photocontrollable fluorescence-switching behavior, which makes this intelligent material an appealing candidate for practical applications.

Solvothermal reactions of AgNO3 with N1,N4-bis(5-fluoropyridin-3-yl)succinamide (bfps) in MeCN afforded the one-dimensional cationic coordination polymer {[Ag(bfps)]NO3}n (1). Upon treatment of 1 with the anionic azo dye orange II (NaOII) in aqueous solution, the NO3– anions of 1 could be gradually exchanged by the OII– anions via an anion-exchange process. The resulting OII anion-exchanged products {[Ag(bfps)](NO3)0.85(OII)0.15}n (2) and {[Ag(bfps)](NO3)0.1(OII)0.9}n (3) were formed by different molar ratios of 1 and the newly formed phase “{[Ag(bfps)](OII)}n” (4), confirmed by PXRD patterns. Relative to those of the precursors 1 and NaOII, complexes 2 and 3 demonstrated enlarged photocurrent responses and reduced dielectric constants and dielectric losses, which could be correlated with the OII– contents in their structures. Complex 3 acquired a stable anodic photocurrent of 12.06 μA, which was 4.9 times higher than that of 1. The dielectric constant (er = 4.2) and dielectric loss (0.002) of 3 were near...

Treatment of N,N-bis(diphenylphosphanylmethyl)-3-aminopyridine (3-bdppmapy) with AgX (X = Br, I, CN, SCN, dicyanamide (dca)) under different reaction conditions afforded seven mononuclear, dinuclear, and polymeric coordination complexes including [Ag4I4(3-bdppmapy)2]n (1), [Ag2I2(3-bdppmapy)3]·CH3OH (2·CH3OH), [Ag2Br(3-bdppmapy)3]Br·4CH3OH (3·4CH3OH), [Ag4(CN)4(3-bdppmapy)3]·2CH3OH (4·2CH3OH), [Ag(3-bdppmapy)2]SCN (5), [Ag(3-bdppmapy)2](dca) (6), and {[Ag4(dca)4(3-bdppmapy)2]·4DMF}n (7). Compound 1 contains a unique two-dimensional (2D) network in which chairlike [Ag4I4] units are interconnected by μ3-3-bdppmapy bridges. Compounds 2 and 4 hold a similar centrosymmetric framework in which two [(3-bdppmapy)AgI] (2) or [(3-bdppmapy)Ag2(CN)2] (4) units are linked by a μ-3-bdppmapy. Compound 3 has a batlike cationic structure in which two Ag/3-bdppmapy units are joined by a pair of μ-Br and μ-3-bdppmapy bridges. Compounds 5 and 6 have a similar cationic mononuclear structure in which the Ag(I) center is chelat...

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...

A novel K2CO3-mediated cyclization and rearrangement of γ,δ-alkynyl oximes for the synthesis of pyridols is described. The process accomplishes an efficient [1,3] rearrangement of the O-vinyl oxime intermediate which is in situ generated from the intramolecular nucleophilic addition of γ,δ-alkynyl oximes. The reaction employs readily accessible starting materials, tolerates a wide range of functional groups, and gives a variety of synthetically challenging pyridols in good yields.

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 iron-catalyzed dehydrogenative [4 + 2] cycloaddition reaction of tertiary anilines and enamides for the synthesis of tetrahydroquinolines with amido-substituted quaternary carbon centers has been developed. The reaction proceeds through iron-catalyzed dehydrogenation of tertiary anilines followed by nucleophilic addition/intramolecular cyclization with enamides to afford tetrahydroquinolines with amido-substituted quaternary carbon centers in good yields. The reaction tolerates a wide range of functional groups and proceeds under mild conditions. The mechanism for the dehydrogenative [4 + 2] cycloaddition has been confirmed by DFT calculations.

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.

Two-dimensional (2D) chalcogenide materials are fundamentally and technologically fascinating for their suitable band gap energy and carrier type relevant to their adjustable composition, structure, and dimensionality. Here, we demonstrate the exfoliation of single-crystal SnS2-xSex (SSS) with S/Se vacancies into an atom-thin layer by simple sonication in ethanol without additive. The introduction of vacancies at the S/Se site, the conflicting atomic radius of sulfur in selenium layers, and easy incorporation with an ethanol molecule lead to high ion accessibility; therefore, atom-thin SSS flakes can be effectively prepared by exfoliating the single crystal via sonication. The in situ pyrolysis of such materials can further adjust their compositions, representing tunable activation energy, band gap, and also tunable response to analytes of such materials. As the most basic and crucial step of the 2D material field, the successful synthesis of an uncontaminated and atom-thin sample will further push ahead the large-scale applications of 2D materials, including, but not limited to, electronics, sensing, catalysis, and energy storage fields.

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.

A one-pot synthesis of multisubstituted 2,3-dihydro-1H-2-benzazepin-1-ones and 3H-2-benzoxepin-1-ones by an I-MCR/Wittig sequence was developed. The reaction of phosphonium salt 3, arylglyoxals 4, amine 5 (or without), and isocyanide 6 produced the 2,3-dihydro-1H-2-benzazepin-1-ones 8 or 3H-2-benzoxepin-1-ones 10 in good yields via a sequential Ugi or Passerini condensation and intramolecular Wittig reaction in the presence of NEt3.

A novel and efficient palladium-catalyzed intramolecular oxidative cyclization of tertiary enamines for the synthesis of 1,3,4-trisubstituted pyrroles and 1,3-disubstituted indoles has been developed. Trifluoroacetic acid plays an important role in the reaction. A series of pyrroles and indoles with substitution patterns that are not easily accessible by traditional routes were synthesized in good yields under mild conditions.

A novel ruthenium-catalyzed cyclization of ketoxime carboxylates with N,N-dimethylformamide (DMF) for the synthesis of tetrasubstituted symmetrical pyridines has been developed. A methyl carbon on DMF performed as a source of a one carbon synthon. And NaHSO3 plays a role in the reaction.

A novel palladium-catalyzed oxidative double carbonylation of o-iodoanilines for the synthesis of isatoic anhydrides has been developed. The reaction employs readily available o-iodoanilines as the starting materials and proceeds under mild conditions. For extension, palladium-catalyzed oxidative carbonylation of anthranilic acids was developed for the synthesis of substituted isatoic anhydrides in high to excellent yields.

Solvothermal reactions of Zn(NO3)2 with tetrakis(4-pyridyl)cyclobutane (tpcb) and 1,4-naphthalenedicarboxylic acid (1,4-H2ndc) and 2,3-naphthalenedicarboxylic acid (2,3-H2ndc) in different solvents led to the formation of three polydimensional coordination polymers {[Zn2(H2O)(1,4-ndc)2(tpcb)]}n (1), {[Zn(1,4-ndc)(tpcb)0.5]}n (2), and {[Zn2(H2O)(2,3-ndc)2(tpcb)]}n (3). Compounds 1–3 were characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and single crystal X-ray diffraction. Compound 1 is a three-dimensional (3D) (3,3)-connected net with a (10·122)·(102·12) Schlafli symbol. Compound 2 holds a 2-fold interpenetrating 3D framework with a (42·62·72)·(4·62·73) Schlafli symbol, which shows hexagonal-prism-like one-dimensional channels. Compound 3 shows a two-dimensional (3,8)-connected network. The solid state luminescent, optical, and thermal stability properties of 1–3 at ambient temperature were also investigated. A comparative study on their photocatalytic activity toward the degradat...

A novel Cu(TFA)2-catalyzed oxidative tandem cyclization/1,2-alkyl migration of readily available enamino amides for the synthesis of pyrrolin-4-ones has been developed. The reaction tolerates a wide range of functional groups and is a reliable method for the rapid synthesis of substituted pyrrolin-4-ones in high yields under mild conditions.

Treatment of [Et4N][Tp*WS3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with [Cu(MeCN)4]PF6 and NH4PF6 (molar ratio = 1:2:1) in excess pyridine (py) produced one discrete trinuclear cluster [Et4N][Tp*WS3Cu2(py)3](PF6)2 (2). Reactions of 1 with [Cu(MeCN)4]PF6, NH4PF6, and 4,4′-bipyridine (4,4′-bipy) (or 1,2-bis(4-pyridyl)ethane (bpea)) (molar ratio = 1:2:1:2) afforded a two-dimensional (2D) [Tp*WS3Cu2]-based cationic polymer {[Tp*WS3Cu2(4,4′-bipy)1.5](PF6)·2MeCN}n (3·2MeCN) and a one-dimensional (1D) [Tp*WS3Cu2]-based cationic polymer {[(Tp*WS3Cu2)2(bpea)3](PF6)2·2DMF}n (4·2DMF), respectively. Analogous reactions of 1 with CuCN, NH4PF6, and 4,4′-bipy (or 1,2-bis(4-pyridyl)ethylene (bpee)) (molar ratio = 1:2:1:2) gave rise to a 2D [Tp*WS3Cu2]-based polymer {[Tp*WS3Cu2(μ-CN)(4,4′-bipy)0.5]·MeCN}n (5·MeCN) and a three-dimensional (3D) [Tp*WS3Cu2]-based anionic polymer {[Et4N][(Tp*WS3Cu2)2{Cu(μ-CN)2.5}2(bpee)]·3MeCN}n (6·3MeCN), respectively. Compounds 2–6 were characterized by elemental analysis, ...

Reactions of N,N-bis(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) with [Ag(MeCN)4]ClO4 or AgX (X = Cl, Br, I, SCN, CN) afforded a family of oligomeric and polymeric complexes: [Ag2(MeOH)(bdppmapy)2](ClO4)2 (1), [AgCl(bdppmapy)] (2), [AgBr(bdppmapy)] (3), [AgI(bdppmapy)] (4), [AgSCN(bdppmapy)] (5), [{(η2-bdppmapy)Ag(μ-CN)AgCN}2(μ-bdppmapy)] (6), [Ag4(μ-CN)4(μ-bdppmapy)] (7), and [Ag2(μ-CN)(μ-bdppmapy)2][Ag5(μ-CN)6] (8). Compounds 1–8 were characterized by elemental analyses, IR spectra, 1H and 31P{1H} NMR, electrospray ionization (ESI) mass spectra, powder X-ray diffraction (XRD), and single-crystal X-ray diffraction. Compounds 1–3 and 5 hold a one-dimensional (1D) chain in which [Ag(MeOH)]+ or [AgX] motifs are linked by bdppmapy bridges. Compound 6 has a tetrameric framework in which two linear [(η2-bdppmapy)Ag(μ-CN)AgCN] fragments are connected by a μ-bdppmapy ligand. Compound 7 contains a 1D staircase chain in which two zigzag [Ag(μ-CN)]n chains are linked by pairs of μ-bdppmapy bridges. Compoun...

Solvothermal reactions of LnCl3·6H2O (Ln = Nd, Eu, Yb) with equimolar amounts of 5,11,17,23-tetrakis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene (H4L) at 90 or 140 °C gave rise to a set of six lanthanide(III) coordination polymers {[Nd2ClL(HCOO)(DMF)3(H2O)]·0.5DMF·MeCN·1.5H2O}n (1), {[Ln2ClL(HCOO)(DMF)]·sol}n (2: Ln = Eu, sol =0.5MeCN·1.5H2O; 3: Ln = Yb, sol = 1.5H2O), and {[H3O][LnL(H2O)]·DMF·MeCN·H2O}n (4: Ln = Nd; 5: Ln = Eu; 6: Ln = Yb). Complexes 1–6 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compounds 1–3 have two-dimensional (2D) networks in which [Nd6Cl4L2(DMF)12(H2O)2] units (1) or [Ln6Cl4L2(DMF)2] (Ln = Eu (2), Yb (3)) are interlinked by the carboxyl groups of formates. Compounds 4–6 exhibit 2-fold interpenetrating 2D networks in which each [Ln4L(H2O)4] “four-flier pinwheel” unit works as a planar eight-connecting node to connect its eight equivalents via four L ligands. The formation of 1–6 provided an interestin...

Protonolysis reactions of [(Me3Si)2N]3Ln(μ-Cl)Li(THF)3 (Ln = Pr, Nd, Sm, Eu) with 3 equiv of 4,6-dimethylpyrimidine-2-thiol (dmpymtH) gave rise to the four Ln(III) pyrimidine-2-thionate complexes Li[Ln(dmpymt)4] (Ln = Pr (1), Nd (2), Sm (3), Eu (4)). Compounds 1−4 were characterized by elemental analysis, IR and 1H NMR spectroscopy, and single-crystal X-ray diffraction. X-ray diffraction analysis shows that the structures of 1−4 are similar and each eight-coordinate Ln(III) ion is chelated by four dmpymt ligands. Complexes 1−4 display excellent catalytic performance in the cyclodimerization of isocyanates to produce substituted ureas via elimination of CO, which represents the first example of lanthanide thiolates exhibiting a high catalytic activity and a high selectivity in the cyclodimerization of isocyanates. The effects of the solvents, temperatures, catalyst loadings, and rare-earth metals on the catalytic activities of the complexes were examined.

Reactions of [Hg(Tab)2](PF6)2 (TabH = 4-(trimethylammonio)benzenethiol) (1) with acetic acid (HAc), propanoic acid (HPro), salicylic acid (HSal), benzoic acid (HBez), malonic acid (H2Mal), oxalic acid (H2Oxa), adipic acid (H2Adi), or methylimindiacetic acid (H2Meida) in the presence of Et3N gave rise to a family of mercury(II)-thiolate-carboxylate compounds, [Hg(Tab)2(Ac)](PF6) · 0.5H2O (2 · 0.5H2O), [Hg(Tab)2(Pro)](PF6) (3), [Hg(Tab)2(Sal)](PF6) · MeOH (4 · MeOH), [Hg(Tab)2(Sal)](Sal) · MeOH (5 · MeOH), [Hg(Tab)2(Bez)](PF6) · H2O (6 · H2O), [Hg(Tab)2(HMal)](Mal)0.5 H2O (7 · H2O), [{Hg(Tab)2}2(μ-Oxa)](PF6)2 H2O (8·2H2O), [{Hg(Tab)2}2(μ-Adi)](PF6)2 (9), [Hg(μ-Tab)(μ-Adi)]2n (10), and [Hg(Tab)2(Meida)] · 2.5H2O (11 · 2.5H2O). These compounds were characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H NMR, and single-crystal X-ray crystallography. Each mercury(II) atom in [Hg(Tab)2](2+) dication of 2-7 is further coordinated by two oxygen atoms from one Ac(-), Pro(-), Sal(-), Bez(-), Mal(2-) or HMal(-) anion, forming a unique seesaw-shaped coordination geometry. In 8 or 9, two [Hg(Tab)2](2+) dications are connected by one bridging oxalate or adipate dianion to generate a dimeric structure with each mercury(II) center adopting a seesaw-shaped geometry. In 10, a pair of octahedrally coordinated mercury(II) atoms are bridged by two sulfur atoms of two Tab ligands to form a [Hg(μ-Tab)2Hg](4+) fragment, which is further connected to its equivalent ones via four adipate dianions, thereby forming a rare two-dimensional network. In 11, the mercury(II) atom in the [Hg(Tab)2](2+) dication is coordinated by one nitrogen and two oxygen atoms from one Meida(2-) dianion to have a rare square pyramidal geometry. The formation of 2-11 from 1 may be applicable to mimicking the interactions of the mercury(II) sites of Hg-MerR and Hg-MT with various amino acids encountered in nature.

Solvothermal reactions of bulk CuSCN with six flexible benzimidazolyl-based ligands with different spacer lengths [(bzim)(CH2)n(bzim)] (bzim = benzimidazolyl; n = 1, mbbm; n = 2, ebbm; n = 3, prbbm; n = 4, bbbm; n = 5, pbbm; n = 6, hbbm) afforded a series of new [CuSCN]n-supported coordination polymers, [(CuSCN)2(mbbm)]n (1), [(CuSCN)2(ebbm)2]n (2), [(Cu(SCN)2(prbbm)]n (3a), [{(CuSCN)2(prbbm)2}·2MeCN]n (3b), [(CuSCN)4(bbbm)3]n (4), [(CuSCN)2(pbbm)]n (5), and [(CuSCN)2(hbbm)]n (6), respectively. Compounds 1−6 were characterized by elemental analysis, IR, and X-ray crystallography. Compound 1, 3a, or 6 possesses the similar staircase-like [CuSCN]n chains that are bridged by mbbm, prbbm, or hbbm to form one one-dimensional (1D) chain with an oblong channel (3a) or two two-dimensional (2D) networks (1 and 6). Compound 2 or 3b consists of a dimeric [CuSCN]2 fragment that serves either as a 4-connecting node to link the other four equivalent ones via two pairs of ebbm bridges to form a 2D (4,4) network (2) or a...

Reactions of (NH4)2[MoOS3] with [Cu(MeCN)4](ClO4) and bis(3,5-dimethylpyrazolyl)methane (dmpzm) (molar ratio = 1:3:3) in MeCN produced a cationic cluster [MoOS3Cu3(dmpzm)3](ClO4) (1). 1 consists of a unique 3D hydrogen-bonded network with empty C3-symmetry cavities. A set of C3 (cyclohexane) or non-C3-symmetry solvent molecules (aniline, N,N′-dimethylformamide, formamide, and water) could recognize these C3-symmetry cavities and smartly fit themselves into them by converting themselves into C3-symmetry species through intriguing ways of symmetry-oriented molecular disorder and trimerlization.

Solvothermal reactions of CuI with 4,4′-dipyridyl disulfide (dpds) and oxalic acid in toluene and acetonitrile at three different time periods gave rise to three Cu/I/S-based coordination polymers, [Cu6(μ-4-SpyH)4I6]n (1), {[Cu2(μ-I)(μ-4-SpyH)3]I}n (2), and [Cu5(μ-4-SpyH)7(μ-I)I4]n (3). The preparation of 1−3 was involved in the in situ formation of the zwitterionic pyridium-4-thiolate (4-SpyH) molecule from the S−S cleavage of the dpds ligand. These compounds were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD), and single crystal X-ray diffraction. Compound 1 contains an adamantine-type [Cu6S4] core that links the neighboring ones via double iodide bridges to form a three-dimensional (3D) diamond-like net. Compound 2 has a one-dimensional (1D) cationic {[Cu2(μ-I)(μ-4-SpyH)3]n}n+ polymeric chain with disordered iodides embedded between chains. Compound 3 contains the [Cu5(μ-I)I4(μ-4-SpyH)7] species that is interconnected with its nei...

A general protocol for the rhodium-catalyzed oxidative carbonylation of arenes to form esters has been developed. A broad substrate scope has been demonstrated allowing carbonylation of electron-rich, electron-poor, and heterocyclic arenes, and the reaction shows wide functional group tolerance and excellent regioselectivities. Up to 96% yield of ortho-substituted aryl or heteroaryl carboxylic esters were obtained with this methodology. The possible mechanism for the rhodium-catalyzed oxidative carbonylation reaction was proposed in this article. Studies show that Oxone play an important role in the transformation.

Treatment of [Et4N]2[(edt) 2 Mo 2 S 2 (μ-S)2] (1) (edt = ethanedithiolate) with equimolar CuBr afforded an anionic hexanuclear cluster [Et4N]2[(edt) 2 Mo 2 (μ-S) 3 (μ 3 -S)Cu]2 ·2CH 2 Cl 2 (2·2CH 2 Cl 2 ). On the other hand, reactions of 1 with 2 equiv of CuBr in the presence of 1,2-bis(diphenylphosphino)methane (dppm) and pyridine (Py) ligands gave rise to two neutral tetranuclear clusters [(edt) 2 Mo 2 O 2 (μ-S)2Cu2(dppm)2] (3) and [(edt) 2 Mo 2 O(μ 3 -S)(μ-S)2Cu2(Py)4] (4), respectively. The reaction of 1 with 2 equiv of CuBr followed by the addition of a mixture of dppm and Py (molar ratio = 1:2) yielded another neutral tetranuclear cluster [(edt) 2 Mo 2 (μ-S) 2 (μ 3 -S)2Cu2(dppm)(Py)]·Py (5 ·Py). Compounds 2-5 have been characterized by elemental analysis, UV-vis spectra, IR spectra, 1 H NMR, and X-ray analysis. The structure of the dianion of 2 can be viewed as having a [Mo 4 S 8 Cu 2 ] core in which two chemically equivalent [Mo 2 (μ-S) 3 (μ 3 -S)(edt) 2 Cu] - anions are linked by two extra Cu-S edt bonds. The molecular structure of 3 may be visualized as being built of one [(edt) 2 Mo 2 X 2 (μ-S) 2 ] 2- dianion and one [Cu 2 (dppm) 2 ] 2+ dication that are connected by a pair of M-μ-S edt bonds. Compound 4 is formed by the affiliation of two Cu(Ι) atoms only at one end of the [(edt) 2 Mo 2 S 2 (μ-S) 2 ] moiety, connecting with the S t atoms and the S edt atom. Cluster 5 ·Py can be viewed as being constructed from the addition of one Cu atom onto the incomplete cubanelike [Mo 2 S 4 Cu] framework through one terminal sulfur and one edt sulfur. Among the four clusters, 3 and 4 have internal mirror symmetry or pseudo mirror symmetry, respectively, while 2 and 5 are asymmetric clusters with racemic formation.

In our working toward the rational design and synthesis of cluster-based suppramolecular architectures, a set of new [WS4Cu4]- or [MoOS3Cu3]-based supramolecular assemblies have been prepared from reactions of preformed cluster compounds [Et4N]4[WS4Cu4I6] (1) and [(n-Bu)4N]2[MoOS3Cu3X3] (2, X = I; 3, X = SCN) with flexible ditopic ligands such as dipyridylsulfide (dps), dipyridyl disulfide (dpds), and their combinations with dicyanamide (dca) anion and 4,4‘-bipy. The cluster precursor 1 reacted with dps or dpds and sodium dicyanamide (dca) in MeCN to produce [WS4Cu4I2(dps)3]·2MeCN (4·2MeCN) and [WS4Cu4(dca)2(dpds)2]·Et2O·2MeCN (5·Et2O·2MeCN), respectively. On the other hand, treatment of 2 with dpds in DMF/MeCN afforded [MoOS3Cu3I(dpds)2]·0.5DMF·2(MeCN)0.5 (6·0.5DMF·2(MeCN)0.5) while reaction of 3 with sodium dicyanamide (dca) and 4,4‘-bipy in DMF/MeCN gave rise to [MoOS3Cu3(dca)(4,4‘-bipy)1.5]·DMF·MeCN (7·DMF·MeCN). Compounds 4·2MeCN, 5·Et2O·2MeCN, 6·0.5DMF·2(MeCN)0.5, and 7·DMF·MeCN have been characteri...

The reaction of AuI with 2 equiv of TabHPF6 [TabH = 4-(trimethylammonio)benzenethiol] in the presence of excess Et3N in dimethylformamide (DMF)/MeOH afforded a binuclear gold(I) complex [Au(Tab)2]2I2·2H2O (1). Anion exchange of 1 with NH4PF6 in DMF gave rise to the more soluble complex [Au(Tab)2]2(PF6)2 (2). Treatment of 2 with K[Au(CN)2] produced a tetranuclear gold(I) complex {[(Tab)2Au][Au(CN)2]}2 (3). Analogous reactions of two known mononuclear complexes [Ag(Tab)2](PF6) (4) and [Hg(Tab)2](PF6)2 (5) with 1 or 2 equiv of K[Au(CN)2] generated one Ag2Au2 complex {[(Tab)2Ag][Au(CN)2]}2 (6) and one Au/Hg complex {[Hg(Tab)2][Au(CN)2]2} (7), respectively. Compounds 1−3, 6, and 7 were fully characterized by elemental analysis, IR spectra, UV−vis spectra, 1H NMR, and single-crystal X-ray crystallography. 1 and 2 have a similar [Au(Tab)2]22+ dimeric structure in which the two [Au(Tab)2]+ cations are connected via one Au−Au aurophilic interaction. In the structure of 3 or 6, each of the two pairs of [M(Tab)2]+ c...

Reaction of trans-[(η5-C5Me5)2Mo2(μ-S)2S2] (1) with 2 equiv of CuI in CH2Cl2 at ambient temperature or in refluxing MeCN afforded two isomeric clusters, [(η5-C5Me5)2Mo2(μ3-S)3S(CuI)2] (2) and [(η5-...

Approaches to the assembly of (η5-C5Me5)WS3Cu3-based supramolecular compounds from two preformed incomplete cubane-like clusters [PPh4][(η5-C5Me5)WS3(CuX)3] (X = CN, 1a; X = Br, 1b) have been inves...

Reactions of Hg(OAc)2 with 2 equiv of TabHPF6 [TabH = 4-(trimethylammonio)benzenethiol] in MeCN/MeOH afforded a mononuclear linear complex [Hg(Tab)2](PF6)2 (1). By using 1 as a precursor, a new family of mercury(II) zwitterionic thiolate complexes, [Hg2(Tab)6](PF6)4.2MeCN (2.2MeCN), [Hg(Tab)2(SCN)](PF6) (3), [Hg(Tab)2(SCN)2] (4), [Hg(Tab)I2] (5), {[Hg(Tab)2]4[HgI2][Hg2I6]}(PF6)2(NO3)4 (6), [Hg(Tab)2][HgI4] (7), [Hg(Tab)2][HgCl2(SCN)2] (8), [Tab-Tab]2[Hg3Cl10] (9), and [Hg2(Tab)6]3(PF6)Cl11 (10), were prepared and characterized by elemental analysis, IR spectra, UV-vis spectra, 1H NMR, and single-crystal X-ray crystallography. The [Hg2(Tab)6]4+ tetracation of 2 or 10 contains an asymmetrical Hg2S2 rhomb with an inversion center lying on the midpoint of the Hg...Hg line. The Hg atom of the [Hg(Tab)2]2+ dication of 3 is coordinated to one SCN-, forming a rare T-shaped coordination geometry, while in 4, the Hg atom of [Hg(Tab)2]2+ is coordinated to two SCN-, forming a seesaw-shaped coordination geometry. Through weak secondary Hg...S coordinations, each cation in 3 is further linked to afford a one-dimensional zigzag chain. The trigonal [Hg(Tab)I2] molecules in 5 are held together by weak secondary Hg...I and Hg...S interactions, forming a one-dimensional chain structure. In 6, the four [Hg(Tab)2]2+ dications, one HgI2 molecule, one [Hg2I6]2- dianion, one PF6-, and four NO3- anions are interconnected by complicated secondary Hg...I and Hg...O interactions, forming a scolopendra-like chain structure. The secondary Hg...I interactions, [Hg(Tab)2]2+ and [HgI4]2- in 7, are combined to generate a one-dimensional chain structure, while [Hg(Tab)2]2+ and [HgCl2(SCN)2]2- in 8 are interconnected by secondary Hg...N interactions to form a one-dimensional zigzag chain structure. Compound 9 consists of two [Tab-Tab]2+ dications and one [Hg3Cl10]4- tetraanion. The facile approach to the construction of 2-8 and 10 from 1 may be applicable to the mimicking of a coordination sphere of the Hg sites of metallothioneins.