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It is well known that diazonium salts (ArN2+) react with phenols (Ar′OH) to give aryl diazoethers or diazo compounds, but their cross-coupling to exclusively access diaryl ethers is challenging. Herein we disclose the Cu-catalyzed etherification of phenols with aryl diazonium salts at room temperature, yielding diaryl ethers in moderate to excellent yields. The advantages of this protocol are mild reaction conditions, availability of reactants, operational simplicity, high tolerance of other functional groups and easy work-up. Its application to the synthesis of complex biological molecules is demonstrated. The reaction proceeds through single-electron transfer, extrusion of nitrogen, oxidative addition, and reductive elimination to give diaryl ether products. [ABSTRACT FROM AUTHOR]

Earth-abundant copper(I) coordination complexes of an imine-phosphine and a diimine have been developed as visible-light photocatalysts. Reaction of [Cu(MeCN)4]BF4 with hetero-bidentate phosphinopyrazole (phpz) ligand R1R2C3HN2PPh3 (R1 = R2 = H (1a); R1 = H, R2 = Me (1b); R1 = H, R2 = Ph (1c); R1 = R2 = Me (1d)) and 2,9-dimethyl-1,10-phenanthroline (dmp) gave four heteroleptic bis-chelate Cu(I) complexes [Cu(dmp)(R1R2C3HN2PPh3)]BF4 (R1 = R2 = H (2a); R1 = H, R2 = Me (2b); R1 = H, R2 = Ph (2c); R1 = R2 = Me (2d)) with distorted tetrahedral geometries. Complexes 2a–2d exhibited broad absorption in the visible spectrum and could facilitate photochemical intermolecular atom-transfer radical addition reactions of CBr4, or CCl3Br, CHI3 to styrenes in yields up to 91% and with a broad substrate scope. The absorption, emission, redox potential and photocatalytic activity were dependent on the substituents on the phpz ligand. Mechanistic studies supported an atom-transfer radical addition (ATRA) mechanism. [ABSTRACT FROM AUTHOR]

We report the discovery of a new noncentrosymmetric superconductor, W4IrC1−x, which adopts a cubic β-Mn type structure for x in the range of 0 to 0.2. This compound is stabilized by interstitial carbon and becomes unstable by annealing or varying the W/Ir ratio. We show that both W4IrC and W4IrC0.8 are weakly coupled type-II superconductors with bulk Tc values of 4.77 and 4.87 K, respectively. Remarkably, their zero-temperature upper critical fields reach 8.3–8.8 T, which approach the Pauli paramagnetic limit of ∼9.0 T. Theoretical calculations indicate that the Fermi level of W4IrC is located at a local maximum of the density of states, which is dominated by the contributions from the W and Ir atoms and significantly enhanced by the spin–orbit coupling. Our study identifies the 5 d element Ir as an optional constituent in forming β-Mn type superconductors. [ABSTRACT FROM AUTHOR]

Herein, six new [Cu(N^N)(P^P)]+/0 complexes with different N-ligands and counteranions, [Cu2(dmp)2(bdppmapy)I2] (1), [Cu2(dmp)2(bdppmapy)(CN)2]·3CH3OH (2), [Cu(dmp)(bdppmapy)](BF4) (3), [Cu(dmp)(bdppmapy)](ClO4) (4), [Cu(phen)(bdppmapy)](BF4) (5), and [Cu(phen)(bdppmapy)](ClO4) (6), have been synthesized and characterized (bdppmapy = N,N-bis[(diphenylphosphino)methyl]-2-pyridinamine, phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline). Single-crystal X-ray diffraction showed that different counteranions help to construct various stacking modes 1D–3D via weak interactions, such as π–π, C–H⋯π and C–H⋯X (X = F, O). Photophysical analysis showed they have yellow-green to yellow-orange emission within a range of 504–569 nm, and excellent photophysical properties with quantum yields from 2.6% (2) to 77% (4). In this study, these results indicate that the π–π stacking and C–H⋯X (X = O, F) weak interactions help to enhance the rigidity of these structures and further improve their luminescence quantum yields. In addition, we have explored the nature of the complexes emission mechanism through theoretical calculations. According to DFT/TD-DFT calculations, the luminescence behavior of the six complexes is ascribed to MLCT or (M + X)LCT. THz spectra were applied to explore the relationship between weak interactions and luminescence. These results have opened up a new direction in the characterization of the properties of luminescent materials. [ABSTRACT FROM AUTHOR]

Five novel mononuclear [Cu(Bphen)(bdppmapy)]X complexes showing photoluminescence were synthesized. The same diphosphine ligand and diimine ligand and different Cu(I) salts were used in the one-pot synthesis of complexes 1–5. These complexes are listed as follows: [Cu(Bphen)(bdppmapy)]CF3SO3 (1), [Cu(Bphen)(bdppmapy)]BF4·0.268CH3OH (2), [Cu(Bphen)(bdppmapy)]ClO4 (3), [Cu(Bphen)(bdppmapy)]I·CH3OH (4) and [Cu(Bphen)(bdppmapy)]Br·2CH3OH (5) (Bphen = 4,7-diphenyl-1,10-phenanthroline, bdppmapy = N,N-bis((diphenylphosphino)methyl)-2-pyridinamine). IR, NMR, elemental analysis, single-crystal X-ray diffraction analysis, UV-vis, fluorescence spectroscopy and terahertz time-domain absorption spectroscopy (THz-TDS) were used to characterize 1–5. Their crystal structures have been elucidated by X-ray crystallography and their photophysical properties have been investigated in detail. These five complexes have a similar coordination center, while their space stacked structures are different, from a 0D dimeric structure to a 3D supramolecular structure. Photophysical studies and density functional theory calculations (DFT) show that the luminescence properties of these five complexes are mainly ascribed to metal-to-ligand charge transfer (MLCT). Among these five complexes, 1 emits luminescence with the highest quantum yield of 36.96% and a lifetime of 11.90 μs at ambient temperature. Different counter-anions lead to the distinction of QYs, maybe due to the influence of weak forces. Terahertz time-domain absorption spectroscopy was used to characterize these ligands and complexes in the range of 0.2–2.4 THz. [ABSTRACT FROM AUTHOR]

Reaction of [(3-bdppmapy)(AuCl)2] with NaHmba (3-bdppmapy = N,N′-bis-(diphenylphosphanylmethyl-3-aminopytidine, H2mba = 2-mercaptobenzoic acid) resulted in a new tetranuclear Au/P/S complex [(3-bdppmapy)2(AuHmba)3(AuCl)] (1). Upon excitation at 370 nm, 1 exhibited solid state, room temperature, green fluorescent emission (QY = 4.7%, τ = 2.58 ns) which was significantly enanced at lower temperatures due to strengthening of the Au–Au interaction. Different ratios of 1 with phosphor N630 in PMMA were used to make thermochromic photoluminescent films and fibres that could be fabricated into an optical thermometer sensitive over temperature ranges 80–300 K and 300–370 K. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Trinuclear complex [Au2Ag(dppmaphen)2(CN)2]PF6 photoluminesces on exposure to low molecular weight alcohols. This emission is likely due to C–H⋯π interactions between the analyte and –PPh2 group, that inhibits non-radiative relaxation of the photoexcited state. Photoluminescene was quenched by removing the analyte under a stream of N2 or replacing it with H2O. This on/off switching was clearly visible, relatively rapid and recyclable. [ABSTRACT FROM AUTHOR]

The synthesis of four heteroleptic dinuclear Cu(I) complexes bearing tetraphosphine and diimine ligands was reported. Complexes 1–3 were successfully obtained through microwave synthesis while complex 4 was synthesized through traditionally stirring at room temperature. These complexes are listed as follows: [Cu2(Dpq)2(dppeda)](ClO4)2·1.5CH2Cl2 (1), [Cu2(neo)2(dppeda)](ClO4)2·1.3CH2Cl2·1.7C4H10O (2), [Cu2(batho)2(dppeda)](ClO4)2·C4H10O (3), and [Cu2(batho)2(dpppda)](ClO4)2·3CH2Cl2 (4) {(Dpq = pyrazino[2,3-f][1,10]phenanthroline, batho = 4,7-diphenyl-1,10-phenanthroline, neo = 2,9-dimethyl-1,10-phenanthroline, dppeda = N1,N1,N2,N2-tetrakis[(diphenylphosphino)methyl]-1,2-ethanediamine, and dpppda = N1,N1,N4,N4-tetrakis[(diphenylphosphino)methyl]-1,4-benzenediamine}. Their crystal structures have been elucidated by X-ray crystallography and their photophysical properties have been investigated in detail. Photophysical studies and time domain density functional theory (TD-DFT) calculations show that the luminescence performance of these four complexes is ascribed to metal-to-ligand charge transfer (MLCT) mixed with ligand-to-ligand charge transfer (LLCT), and complex 2 shows green emission at 574 nm with the highest quantum yield of up to 52.80%. In addition, the research of photoluminescence properties under the guidance of terahertz spectroscopy technology leads to the preliminary discovery of a correlation between crystal packing and luminescence. It is found that the terahertz spectrum and absorption peak are strongly interdependent on C–H⋯π and π⋯π interactions, and the external weak interactions have negative effects on the luminescence performance. Herein, we predict that the terahertz spectroscopy analysis establishes a bridge between weak interactions (C–H⋯π and π⋯π interactions) and the photoluminescence properties, and puts forward a problem that should be noticed in designing Cu(I) complexes. [ABSTRACT FROM AUTHOR]

Tetraphosphine ligand dpppda reacts with AgNO3 to generate two 1D coordination polymers containing cubic and chair-like [Ag4(NO3)4] clusters. ESR spectroscopy supported by DFT calculations indicated the presence of dpppdaṖ+, a Wurster's blue – like radical cation formed by intramolecular ligand-to-metal charge transfer (LMCT). This LMCT results in higher AgI→ Ag0 potentials and good photocurrent responses. [ABSTRACT FROM AUTHOR]

A high symmetry heterothiometallic cluster-based 3D framework of composition [WS4Cu4(μ-CN)2(bpea)2]·1.5DMF was obtained from the combination of (NH4)2WS4, CuCN and 1,2-bis(4-pyridyl)ethane (bpea). It holds an unusual topology with [WS4Cu4]2+ clusters linked by CN− and bpea bridging ligands. An interesting feature of this cubic structure is the presence of isolated hexagonal channels that extend in four distinct directions. Its desolvated sample demonstrated high performance in the adsorption of iodine from solution. [ABSTRACT FROM AUTHOR]

A new P–N hybrid ligand N-diphenylphosphanylmethyl-3-aminopyridine (3-dppmapy) is synthesized and allowed to react with six silver oxysalts including AgTFA (TFA = trifluoroacetic), AgOTF (OTF = trifluoromethanesulfonic), AgNO3, Ag2SO4, AgBz (Bz = benzoate) and AgSal (Sal = salicylate). The reactions result in the formation of two dinuclear complexes [Ag2(Ox)2(3-dppmapy)2] (1, Ox = TFA; 2, Ox = OTF) and four 1D coordination polymers Ag(μ-η2-NO3)(3-dppmapy)·EtOH (3·EtOH), [Ag2(μ-η,η-SO4)(3-dppmapy)2]·CHCl3 (4·CHCl3), [Ag(μ-η2-Bz)(3-dppmapy)] (5) and [Ag(μ-η2-Sal)(3-dppmapy)] (6). All six compounds have energy bands between 3.11–3.43 eV which is in the range of semiconductive materials, whereas only 6 exhibits good stability in water solution under UV irradiation. In the aqueous phase, 6 exhibits high photocatalytic performance in the degradation of eriochrome black T (EBT), amido black (AB) and nigrosin (NO), and also shows relatively prompt anodic photocurrent responses. [ABSTRACT FROM AUTHOR]

Reactions of Cd(NO3)2·4H2O with 1,2,4,5-tetrakis(4-pyridylvinyl)benzene (4-tkpvb) and 5-tert-butylisophthalic acid (5-tert-H2BIPA), 1,3,5-benzenetricarboxylic acid (1,3,5-H3BTC) or 1,4-naphthalenedicarboxylic acid (1,4-H2NDC) under solvothermal conditions afforded three two-dimensional (2D) Cd(ii) coordination polymers [Cd(4-tkpvb)(5-tert-BIPA)]n (1), [{Cd(4-tkpvb)(1,3,5-HBTC)}·0.5DMF]n (2) and [Cd(4-tkpvb)(1,4-NDC)]n (3). Compounds 1–3 were structurally characterized by IR, elemental analysis, powder X-ray diffraction, and single crystal X-ray diffraction. Compounds 1–3 possess unique 2D networks in which 1D double chains [Cd2L2]n (L = 5-tert-BIPA or 1,3,5-HBTC) (1–2) or 1D linear chains [Cd(1,4-NDC)]n (3) are linked by 4-tkpvb ligands. Upon UV light excitation, a 4-tkpvb solution in DMF showed an emission band centered at 446 nm with a shoulder at 475 nm. The addition of Hg2+ ions into the 4-tkpvb solution in DMF remarkably changed its colour from colourless to yellow under natural light, or from blue to grey yellow under UV light, which were clearly visible to the naked eye. Compounds 1–3 suspended in water could emit yellow-green light under UV light irradiation. The representative compound 1 was confirmed to be an uncommon multi-responsive luminescent sensor for Hg2+, CrO42− and Cr2O72− ions in water by the luminescence quenching method. The detection limits for these species were 0.15 μM (Hg2+), 0.08 μM (CrO42−) and 0.12 μM (Cr2O72−), respectively. The luminescence quenching mechanism studies revealed that these quenching processes were involved in either the interaction of Hg2+ with free pyridyl groups in 1 or the overlap between the absorption band of CrO42− or Cr2O72− and the excitation and/or emission bands of 1. [ABSTRACT FROM AUTHOR]

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=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. [ABSTRACT FROM AUTHOR]

A novel and facile iron-catalyzed cyclization of ketoxime acetates and aldehydes for the green synthesis of substituted pyridines has been developed. In the presence of a FeCl3 catalyst, this reaction exhibited a good functional group tolerance to produce 2,4,6-triarylsubstituted symmetrical pyridines in high yields in the absence of any additive. A gram-scale reaction sequence was performed to demonstrate the scaled-up applicability of this synthetic method. [ABSTRACT FROM AUTHOR]

An acylhydrazone zinc porphyrin P1 and its coordination polymers (CPs, denoted as P1M, M = Mn, Co, Ni, Cu, Zn) with different metal ions (Mn2+, Co2+, Ni2+, Cu2+ and Zn2+) were synthesized. Then these coordination polymers were assembled into bilayer structured supramolecular chromophores through axially coordinating with anchoring porphyrin AP, and their performance in dye sensitized solar cells was investigated. Our results reveal that the bilayer structured supramolecular chromophore based solar cells show significantly improved photocurrent conversion efficiency. Particularly, P1Mn and P1Zn based solar cells showed a relatively higher short circuit current density (JSC) due to their broad absorption bands and remarkable light harvesting abilities. Meanwhile, the VOC values of the cells fabricated with the bilayered chromophores slightly decreased. Electrochemical impedance spectroscopy (EIS) in combination with charge extraction (CE) and transient photovoltage decay (TPD) measurements indicates that the decreased VOC resulted from the vigorous electron recombination and the downward shifted conduction band edge (ECB) of titania. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Reactions of a P–N hybrid ligand, N,N-bis(diphenylphosphanylmethyl)-3-aminopyridine (3-bdppmapy), with silver oxysalts including AgNO3, AgOAc, AgBz (Bz = benzoate) and AgSal (Sal = salicylate) under different reaction conditions give rise to seven coordination compounds {[Ag4(μ–η,η-NO3)2(μ–η,η2-NO3)2](3-bdppmapy)2}n (1), {[Ag4(μ–η,η2-NO3)4](3-bdppmapy)2}n (2), {[Ag2(μ–η2-OAc)(μ–η,η2-OAc)]2(3-bdppmapy)2}n (3), [Ag2(Bz)(μ–η,η2-Bz)(H2O)]2(3-bdppmapy)2 (4), {[Ag4(μ–η2-Bz)2(μ–η,η2-Bz)2](3-bdppmapy)2}n (5), {Ag(Sal)(3-bdppmapy)}n (6) and {[Ag4(Sal)2(μ–η,η2-Sal)2](3-bdppmapy)2}n (7). Single crystal X-ray analyses reveal that 1, 5 and 7 have similar 1D chain structures constructed by [Ag4(μ–η2-Ox)2(μ–η,η2-Ox)2] units (1: Ox− = NO3−; 5: Ox− = Bz−) or [Ag4(Sal)2(μ–η,η2-Sal)2] units (7) and double 3-bdppmapy bridges. Compound 2 has a 2D layer structure derived from [Ag4(μ–η,η2-NO3)4] units and single 3-bdppmapy bridges. 3 displays another 2D layer structure formed by [Ag2(μ–η2-OAc)(μ–η,η2-OAc)] units and double 3-bdppmapy bridges. 4 shows a discrete tetranuclear structure formed by two [Ag2(Bz)(η,η2,μ-Bz)(H2O)] units and a pair of 3-bdppmapy bridges, while 6 adopts a 1D chain composed by [AgSal] units and single 3-bdppmapy bridges. 6 and 7 as representative samples display high catalytic activity toward the photodegradation of rhodamine B (RhB) in water. Compound 7 shows a better photocatalytic performance than that of 6, which correlates well with the differences in their anodic photocurrent responses and their HOMO–LUMO energy gaps derived from the density function theory (DFT) calculations. The formation of 6 and 7 from AgSal and 3-bdppmapy provides a new approach to the design and assembly of Ag(i)-supported CPs with interesting structural architectures and higher photocatalytic activity. [ABSTRACT FROM AUTHOR]

We prepared in this work an anchoring porphyrin and a series of hat-porphyrins. The zinc atom of the hat-porphyrins can be coordinated axially with the pyridine moiety of the anchoring porphyrin which is anchored on the titania surface by a carboxyl group. The structures of the assemblies were confirmed using computational calculations, transmission electron microscopy (TEM) and energy dispersive spectrometry (EDS). Solar cell devices of the monomer anchoring porphyrin and its assemblies were fabricated and the photovoltaic performances were measured under standard AM 1.5 sunlight irradiance. We found that the assembly devices showed higher JSC and lower VOC than that of the monomer anchoring porphyrin device. However, the comprehensive influence of JSC and VOC led to an enhancement in the solar-to-electric power-conversion efficiency (PCE) of the assemblies. We also studied the variation of JSC and VOC using electronic absorption and emission spectroscopy, charge extraction measurements, transient photovoltage decay measurements and electrochemical impedance spectroscopy. [ABSTRACT FROM AUTHOR]

A novel and efficient copper-catalyzed radical cross-coupling of 1,3-dicarbonyl compounds with terminal alkenes for the synthesis of tetracarbonyl compounds with a quaternary carbon atom has been developed. Mechanistically, this transformation involves the construction of two C–C bonds and two C=O bonds in a one-pot process. The reaction tolerates a wide range of functional groups and proceeds under mild conditions. [ABSTRACT FROM AUTHOR]

Instant adsorption of Congo Red (CR) by a 1D coordination polymer, [(H2L)0.5][Zn(1,2,3-BTA)(H2O)]·2H2O (1·2H2O), leads to the formation of a unique dye composite 1·0.75CR·6H2O, which demonstrates a remarkably enhanced photocurrent response compared to that of its precursor. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of HAuCl4·4H2O with a P–S hybrid ligand N,N-bis(diphenylphosphanylmethyl)-amino-thiocarbamide (dppatc) at 80 °C and 115 °C produced two Au–P–S complexes, [Au2(dppatc)2]Cl2 (1) and [Au2(dppmt)2]n (2) (dppmtH = (diphenylphosphino)methanethiol). 1 and 2 were characterized by elemental analyses, IR and UV-vis spectra, thermal-gravity analyses, powder X-ray diffraction and single crystal X-ray diffraction analyses. Compound 1 contains a dinuclear [Au2(dppatc)2]2+ dication, while 2 has a one-dimensional chain formed by Au…Au aurophilic interactions. Compounds 1 and 2 exhibited excellent catalytic activity toward the photodegradation of nitrobenzene, p-nitrophenol and 2,4-dinitrophenol in aqueous solutions. The degradation reactions followed the zero-order kinetic model, in which the three nitroaromatics could be converted into CO2 and H2O in 92–96% yields. [ABSTRACT FROM AUTHOR]

In this work, a metal-mediated assembling strategy has been used to organize a series of new assemblies based on tetrapyridylporphyrin (ZnP) on nanostructured TiO2 electrode surfaces, wherein the metal ions (M, M = Zn2+, Cd2+, Hg2+ and Mn2+) bridge the pyridyl units of ZnP and (E)-4-[(pyridin-4-ylmethylene)- amino]benzoic acid (A), resulting in a ZnP-M-A assembled mode. The assembled structures were characterized by transmission electron microscopy (TEM), computational calculations, energy-dispersive X-ray spectroscopy (EDX), IR, UV-vis absorption and fluorescence spectra. The performances of the assembly-sensitized solar cells were also measured under an irradiance of 100 mW cm-2 AM 1.5G sunlight. Photoelectrochemical results reveal a relatively large photocurrent of the ZnP-Mn-A device. Simultaneously, a large open-circuit photovoltage and a significantly improved conversion efficiency of the ZnP-Zn-A device are also observed. These findings may serve as another good testing ground for the fabrication of supramolecular solar cells in future. [ABSTRACT FROM AUTHOR]

Reactions of [Et4N][Tp*MoS(S)4] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with 3 equiv. of CuX (X = Cl, Br, I, CN) or [Cu(MeCN)4]ClO4 in CH2Cl2–MeCN or CH2Cl2–DMF afforded [Et4N]2[Tp*Mo(μ3-S)3(CuCl)3(μ3-Cl)] (2), [Et4N][Tp*Mo(μ3-S)3(CuX)3] (3: X = Br; 4: X = I), [Et4N][Tp*MoO(μ-S)2(CuX)] (5: X = I; 6: X = CN) and [Tp*Mo(μ3-S)3Cu3(μ3-S′)]4 (7). Compounds 2–7 were characterized by elemental analysis, IR spectra, UV-vis spectra, 1H NMR, electrospray ion mass spectra (ESI-MS) and X-ray crystallography. The cluster dianion of 2 has a complete cubane-like [Tp*Mo(μ3-S)3(CuCl)3(μ3-Cl)] structure while the anion of 3 or 4 consists of an incomplete cubane-like [Tp*Mo(μ3-S)3(CuX)3] structure. The anion of 5 or 6 has a binuclear structure, in which one [Tp*MoO(μ-S)2] moiety and one CuX unit are linked by a pair of μ-S atoms. The structure of 7 may be considered as a supercube whose eight corners are occupied by four incomplete cubane-like [Tp*Mo(μ3-S)3Cu3] fragments and four μ3-S′ atoms. The third-order nonlinear optical (NLO) properties of 2–6 in DMF were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80 fs pulse width at 800 nm. Compounds 2–6 exhibited good NLO performances and their NLO responses were enhanced relative to that of 1. [ABSTRACT FROM AUTHOR]

In this paper, a novel time-resolved fluoroimmunoassay (TRFIA) protocol using magnetic particles for the simultaneous determination of α-fetoprotein (AFP) and the free β-subunit of human chorionic gonadotropin (free β-hCG) in human serum is described. The new approach uses magnetic particles as an immobilization matrix and means of separation, while the luminescent europium and samarium chelates are used as probes. The proposed method was evaluated via a single-step, sandwich-type TRFIA immunoassay of AFP and free β-hCG as model analytes in serum. With the advantages of magnetic particles, the TRFIA immunoassay exhibited a wide dynamic range for AFP of 0.1–750 ng mL−1, with a lower detection limit of 0.05 ng mL−1. The dynamic range for free β-hCG was 0.16–450 ng mL−1, with a lower detection limit of 0.08 ng mL−1. Satisfactory specificity, reproducibility, and recovery of the immunoassay were demonstrated. Good correlations were obtained in the analysis of 446 human serum samples between the proposed method and a commercial TRFIA kit. These results demonstrate the feasibility and potential of the new method as a rapid and highly sensitive immunoassay that could be developed into a platform for multi-analyte determinations in clinical practice. [ABSTRACT FROM AUTHOR]

Treatment of [Et4N][Tp*W(μ3-S)3(CuBr)3] (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) (1) with an excess of α-methylpyridine (α-MePy) and NH4PF6in CH2Cl2afforded a cationic cluster [Tp*W(μ3-S)3Cu3(α-MePy)3(μ3-Br)](PF6) (2) while the reaction of 1with an excess of 1,4-pyrazine (1,4-pyz) and NH4PF6in MeCN–CH2Cl2at 65 °C produced a polymeric cluster [Tp*W(μ3-S)3Cu3(1,4-pyz)((1,4-pyz)0.5)2(μ3-Br)][Tp*W(μ3-S)3(CuBr)3] (3). Reactions of 1with melamine (MA) in 1 : 1 or 1 : 2 gave rise to another polymeric cluster [{Tp*W(μ3-S)3Cu3Br(μ3-Br)}2(MA)2] (4) and a neutral cluster [Tp*W(μ3-S)3Cu3Br(μ3-Br)(MA)2] (5), respectively. Compounds 2–5were characterized by elemental analysis, IR spectra, UV-vis spectra, 1H NMR, electrospray ionization (ESI) mass spectra and X-ray crystallography. The cation of 2has a cubane-like [Tp*W(μ3-S)3Cu3(μ3-Br)] structure with each α-MePy ligand coordinated at one Cu(i) center. For 3, each [Tp*W(μ3-S)3Cu3(μ3-Br)] core is interconnected by 1,4-pyz bridges to form a 1D cationic zigzag chain with the [Tp*W(μ3-S)3(CuBr)3]−anions arranged along its two sides. For 4, each [Tp*W(μ3-S)3Cu3(μ3-Br)] core is interlinked by MA bridges to afford a 1D spiral chain. 5adopts a cubane-like [Tp*W(μ3-S)3Cu3(μ3-Br)] structure in which one terminal Br and two MA ligands are coordinated at three Cu centers. The third-order nonlinear optical (NLO) properties of 1–5in DMF were investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 80 fs pulse width at 800 nm. Compounds 1–5exhibit good NLO responses, and 3and 4possess the largest second-order hyperpolarizability γvalues among the known W/Cu/S clusters bearing the [Tp*WS3] unit. [ABSTRACT FROM AUTHOR]

A facile and efficient method for the synthesis of substituted pyrroles from enaminoesters and nitroolefins is reported. This general procedure provides a wide variety of multisubstituted pyrroles in good to excellent yields under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The solvothermal reactions of BiI3, KI, I2, 4,4′-bipyridine (4,4′-bipy), and a small amount of water in alcohol and acetonitrile produced four bipyridinium iodobismuthates {[MQ]3[Bi2I6(μ-I)3][Bi2I6(μ-I)2(MQ)2]3} (1, MQ+= N-methyl-4,4′-bipyridinium), {[EQ]3[Bi2I6(μ-I)3][Bi2I6(μ-I)2(EQ)2]3} (2, EQ+= N-ethyl-4,4′-bipyridinium), [MV][BiI5] (Eur. J. Inorg. Chem., 2010, 5326) (3, MV2+= N,N′-dimethyl-4,4′-bipyridinium), and [EV]2[Bi4I10(μ-I)4(μ3-I)2] (4, EV2+= N,N′-diethyl-4,4′-bipyridinium). In these reactions, 4,4′-bipy was partly or completely alkylated by alkyl groups generated from the cleavage of C–O bond of alcohols, forming the N-alkyl-4,4′-bipyridinium cation (Q+) and the N,N′-dialkyl-4,4′-bipyridinium dication (V2+), respectively. Compounds 1–4were characterized by elemental analysis, IR, 1H NMR and single-crystal X-ray diffraction analysis. The optical, electrical conductive and dielectric properties of these compounds were investigated. The dielectric constants of the Q+-based compounds were larger than the values of the V2+-based ones, which showed that the weak electrostatic interactions in the structures may benefit the polarizability of molecules, thereby resulting in a larger dielectric response of the structures under an external electric field, while the strong electrostatic interactions between the positive and negative charge units would lead to a low dielectric constant (low-k) behavior of these compounds. [ABSTRACT FROM AUTHOR]

Reactions of a gold(i) thiolate complex [Au(Tab)2]2(PF6)2(Tab = 4-(trimethylammonio)benzenethiolate) with equimolar 1,2-bis(diphenylphosphine)ethane (dppe), 1,3-bis-(diphenylphosphine)propane (dppp) or 1,4-bis-(diphenylphosphine)butane (dppb) in MeOH–DMF–CH2Cl2gave rise to three polymeric complexes [Au2(Tab)2(dppe)]2(PF6)4·2MeOH (1·2MeOH), [Au2(Tab)2(dppp)]Cl2·0.5MeOH·4H2O (2·0.5MeOH·4H2O), and [Au4(μ-Tab)2(Tab)2(dppb)](PF6)4·4DMF (3·4DMF), respectively. Analogous reaction of 1with dppb in DMF/C2H4Cl2produced one tetranuclear complex [Au2(μ-Tab)(Tab)2]2Cl4·2DMF·4H2O (4·2DMF·4H2O). Complexes 1–4were characterized by elemental analysis, IR spectra, UV-vis spectra, 1H and 31P{1H} NMR and single crystal X-ray analysis. Compounds 1and 2consist of [Au(Tab)]2dimeric fragments that are bridged by dppe or dppp ligands to form a 1D linear chain extending along the aaxis. For 3, each [Au4(Tab)2(μ-Tab)2] fragment is linked by a pair of dppb ligands to afford another 1D chain extending along the caxis. For 4, the four [Au(Tab)]+fragments are linked by two Au–Au bonds and two doubly bridging Tab ligands to form a {[Au(Tab)]4(μ-Tab)2} chair-like cyclohexane structure. Hydrogen-bonding interactions in 2and 4lead to the formation of interesting 2D hydrogen-bonded networks. The luminescent properties of 1–4in solid state were also investigated. [ABSTRACT FROM AUTHOR]

Four 1,3-benzenedicarboxylic acid derivatives, with substituted R (OH, COOH, NO2, Me) groups at the 5-position, were employed to explore their effect on the construction of supramolecular assemblies. Four coordination polymers, [Zn(OH2)(5-HO-1,3-BDC)(1,4-bpeb)]n(1), [Zn(1,3,5-HBTC)(1,4-bpeb)]n(2), {[Zn(5-NO2-1,3-BDC)(1,4-bpeb)]·2(H2O)0.5}n(3), and [Zn(5-Me-1,3-BDC)(1,4-bpeb)]n(4) (1,4-bpeb = 1,4-bis[2-(4-pyridyl)ethenyl]benzene, 5-HO-1,3-BDC = 5-hydroxy-1,3-benzenedicarboxylate, 1,3,5-H3BTC = 1,3,5-benzenetricarboxylate, 5-NO2-1,3-BDC = 5-nitro-1,3-benzenedicarboxylate, 5-Me-1,3-BDC = 5-methyl-1,3-benzenedicarboxylate) were prepared by the hydrothermal reactions of Zn(NO3)2·6H2O with 1,4-bpeb and 5-HO-1,3-H2BDC, 1,3,5-H3BTC, 5-NO2-1,3-H2BDC or 5-Me-1,3-H2BDC. All these compounds were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. The structure of 1has a 3D H-bonded structure derived from linking 1D comb-like [Zn(OH2)(5-HO-1,3-BDC)(1,4-bpeb)]nchains viaintermolecular H-bonding interactions between the coordinated H2O molecule and 1,4-bpeb or one COO−group and between the OH group and the other COO−group. 2has a 3D H-bonded net based on holding 2D [{Zn2(1,3,5-HBTC)2}4]nlayers through intermolecular H-bonding interactions between 1,4-bpeb and the uncoordinated COOH group. 3could be considered as a 6-fold interpenetrating 3D H-bonded supramolecular framework constructed by linking 2D [Zn4(5-NO2-1,3-BDC)4(1,4-bpeb)4]nnetworks through intermolecular H-bonding interactions between the water solvent molecules and the NO2group. 4has a 3-fold interpenetrating 3D framework in which each 2D (4,4) [Zn4(5-Me-1,3-BDC)4(1,4-bpeb)4]nnetwork is interpenetrated by two other equivalent nets. The Schläfli symbols for the four supramolecular frameworks are 41263, (4·62)2(426687), (63)(658) and 4462, respectively. The thermal stability and photoluminescent properties of 1–4were also investigated. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of CuI with four flexible N-heterocyclic ligands, 1,2-bis(4-pyridyl)ethane (bpe), 1,1′-(1,4-butanediyl)bis-1H-benzimidazole (bbbm), 1,1′-(1,4-butanediyl)bis-1H-benzotriazole (bbbt), and 1,1′-(1,5-pentanediyl)bis-1H-benzimidazole (pbbm), afforded four new [CunIn]-based coordination polymers, [Cu3I(μ-I)(μ3-I)(bpe)3]n(1), {[CuI(bbbm)1.5]·0.25MeCN}n(2), and [Cu4(μ3-I)4L2]n(3: L = bbbt; 4: L = pbbm), respectively. Compounds 1–4were characterized by elemental analysis, IR and X-ray crystallography. 1consists of an unique 2D network in which 1D [CuI(bpe)]nzigzag chains are embroidered alternatively onto the two faces of a 2D [Cu4(μ-I)2(μ3-I)2(bpe)2]nlayer through pairs of bpe bridges. 2contains a 66-membered metallomacrocyclic [CuI(bbbm)1.5]6unit that fuses with its neighbouring ones viasharing Cu atoms to form a 2D (6,3) layer network. 3or 4contains a cubanelike [Cu4(μ3-I)4] core, which works as a cross-shaped four-connecting node to link its four equivalent units to form a 2D (4,4) cross-shaped network (3) or acts as a Y-shaped three-connecting node to connect its three equivalent ones to form a 1D double chain (4). In addition, the photoluminescent properties of 1–4in solid state at ambient temperature were also investigated. [ABSTRACT FROM AUTHOR]

Reactions of trans-[(η5-C5Me5)2Mo2S2(μ-S)2] (1) with 2 equiv. of [Cu(MeCN)4]X (X = PF6−, ClO4−) produced two acetonitrile-coordinated cubane-like cationic clusters [(η5-C5Me5)2Mo2(μ3-S)4Cu2(MeCN)2]X2(X = PF6−(2), ClO4−(3)). Treatment of 2or 3with 4,4′-bipyridine (4,4′-bipy) or trans-1,2-bis(4-pyridyl)ethylene) (bpee) afforded two polymeric clusters {[(η5-C5Me5)2Mo2(μ3-S)4Cu2(L)]X2}n(4: L = 4,4′-bipy, X = PF6−; 5: L = bpee, X = ClO4−), while analogous reactions of 2or 3with 1,2-bis(4-pyridyl)ethane (bpea), 1,2-bis(diphenylphosphine)ethane (dppe), or 1,4-bis-(diphenylphosphine)butane) (dppb) formed three dimeric clusters [(η5-C5Me5)2Mo2(μ3-S)4Cu2(L)]2X4(6: L = bpea; X = PF6−; 7: L = dppe, X = ClO4−; 8: L = dppb, X = ClO4−). Clusters 2–8consist of a cubane-like [(η5-C5Me5)2Mo2(μ3-S)4Cu2] core with each Cu being coordinated by one labile MeCN molecule (2, 3) or by bridging dipyridyl or diphosphino ligands (4–8). 4or 5has a 1D zigzag chain structure while 6–8contain cyclic dimeric structures. The third-order non-linear optical (NLO) properties of 2–8in MeCN were investigated by Z-scan technique at 532 nm. These compounds showed strong third-order NLO absorption effects and self-defocusing properties, and their NLO performances were remarkably enhanced relative to those of 1. [ABSTRACT FROM AUTHOR]

A novel and efficient method for the oxidation of 2-arylindoles to synthesize 2-arylbenzoxazinones utilizing oxone as the sole oxidant has been developed. The reaction tolerates a wide range of functional groups and allows quick and atom-economical assembly of a variety of valuable 2-arylbenzoxazinones in high yields. [ABSTRACT FROM AUTHOR]

Reactions of [Et4N][TpMoS(S4)] with three equiv. of CuI in MeCN or in pyridine gave rise to one dicubane and one tetracubane anionic clusters, [Et4N]2[{TpMo(μ3-S)3Cu3I}2(μ-I){Cu(μ-I)2(μ4-I)2}] and [PyH][{TpMo(μ3-S)4Cu3}4(μ12-I)], and their third-order nonlinear optical (NLO) responses were greatly enhanced relative to that of the precursor. [ABSTRACT FROM AUTHOR]

Reactions of [H4L][PF6]4with 4 equiv. of Mn(OAc)2·4H2O in the presence of air gave rise to a mononuclear Mn(iii)–superoxo complex [Mn(iii)L(O2)(H2O)](PF6)2, which contains a bowl-shaped cationic structure with a D4dsymmetry. It has an unprecedented linear end-on Mn(iii)–O2unit and exhibited good efficiency and selectivity in the catalytic oxidation of alkenes with O2plus isobutyraldehyde under mild conditions. [ABSTRACT FROM AUTHOR]

Reactions of Cu(OAc)2·H2O with dmnpzH in EtOH produce a heptanuclear copper(ii) pyrazolate complex [Cu7(OH)2(OAc)6(dmnpz)6(EtOH)6], which is able to undergo a SCSC structural transformation from a lower symmetry structure to a higher symmetry structure viareplacement of ligated-EtOH molecules with MeOH; both complexes along with the solvent-free species exhibit high catalytic activity in the polymerization of MMA. [ABSTRACT FROM AUTHOR]

Earth-abundant copper(I) coordination complexes of an imine-phosphine and a diimine have been developed as visible-light photocatalysts. Reaction of [Cu(MeCN) 4 ]BF 4 with hetero-bidentate phosphinopyrazole (phpz) ligand R 1 R 2 C 3 HN 2 PPh 3 (R 1 = R 2 = H (1a); R 1 = H, R 2 = Me (1b); R 1 = H, R 2 = Ph (1c); R 1 = R 2 = Me (1d)) and 2,9-dimethyl-1,10-phenanthroline (dmp) gave four heteroleptic bis-chelate Cu(I) complexes [Cu(dmp)(R 1 R 2 C 3 HN 2 PPh 3 )]BF 4 (R 1 = R 2 = H (2a); R 1 = H, R 2 = Me (2b); R 1 = H, R 2 = Ph (2c); R 1 = R 2 = Me (2d)) with distorted tetrahedral geometries. Complexes 2a-2d exhibited broad absorption in the visible spectrum and could facilitate photochemical intermolecular atom-transfer radical addition reactions of CBr 4 , or CCl 3 Br, CHI 3 to styrenes in yields up to 91% and with a broad substrate scope. The absorption, emission, redox potential and photocatalytic activity were dependent on the substituents on the phpz ligand. Mechanistic studies supported an atom-transfer radical addition (ATRA) mechanism.

Reaction of [(3-bdppmapy)(AuCl) 2 ] with NaHmba (3-bdppmapy = N , N '-bis-(diphenylphosphanylmethyl-3-aminopytidine, H 2 mba = 2-mercaptobenzoic acid) resulted in a new tetranuclear Au/P/S complex [(3-bdppmapy) 2 (AuHmba) 3 (AuCl)] (1). Upon excitation at 370 nm, 1 exhibited solid state, room temperature, green fluorescent emission (QY = 4.7%, τ = 2.58 ns) which was significantly enanced at lower temperatures due to strengthening of the Au-Au interaction. Different ratios of 1 with phosphor N630 in PMMA were used to make thermochromic photoluminescent films and fibres that could be fabricated into an optical thermometer sensitive over temperature ranges 80-300 K and 300-370 K.

Trinuclear complex [Au2Ag(dppmaphen)2(CN)2]PF6 photoluminesces on exposure to low molecular weight alcohols. This emission is likely due to C-Hπ interactions between the analyte and -PPh2 group, that inhibits non-radiative relaxation of the photoexcited state. Photoluminescene was quenched by removing the analyte under a stream of N2 or replacing it with H2O. This on/off switching was clearly visible, relatively rapid and recyclable.