Search

Herein, a series of Cu, Ni catalysts were synthesized using mesoporous SiO2 (MCM‐41) and fumed SiO2 as supports for the catalytic hydrogenation of furfural (FF). The MCM‐41 support facilitated the high dispersion of Cu, Ni nanoparticles (NPs), and the hydrogenation products are primarily in the form of alcohols. For fumed SiO2, the proper amounts of acid sites contributed to the better selectivity of 2‐methyltetrahydrofuran(2‐MTHF). Hydrogenation results showed that the 10Cu10Ni/MCM‐41 catalyst afforded a 93.6 % yield of tetrahydrofurfuryl alcohol (THFA), while the 10Cu10Ni/SiO2 catalyst afforded a 61.73 % yield of 2‐MTHF and a 31.63 % yield of THFA. Meanwhile, it is also found that impregnating nickel salt before copper salt is more likely to promote the formation of deep hydrogenation products. Cyclic experiments indicate that developing a one‐step hydrogenation process with selective production of fully hydrogenated products is still a daunting and challenging task. [ABSTRACT FROM AUTHOR]

In this study, a novel approach for the tertiary α‐alkylation of ketones using alkanes with electron‐deficient C─H bonds is presented, employing a synergistic catalytic system combining inexpensive copper salts with aminocatalysis. This methodology addresses the limitations of traditional alkylation methods, such as the need for strong metallic bases, regioselectivity issues, and the risk of over alkylation, by providing a high reactivity and chemoselectivity without the necessity for pre‐functionalized substrates. The dual catalytic strategy enables the direct functionalization of C(sp3)─H bonds, demonstrating remarkable selectivity in the presence of conventional C(sp3)─H bonds that are adjacent to heteroatoms or π systems, which are typically susceptible to single‐electron transfer processes. The findings contribute to the advancement of alkylation techniques, offering a practical and efficient route for the construction of C(sp3)─C(sp3) bonds, and paving the way for further developments in the synthesis of complex organic molecules. [ABSTRACT FROM AUTHOR]

Phenolic resin pyrolytic carbons were obtained by catalytic pyrolysis of phenolic resin at 500 °C, 600 °C, 700 °C, and 800 °C for 3 h in an argon atmosphere using copper nitrate as a catalyst precursor. The effects of copper salts on the pyrolysis process of phenolic resin as well as the structural evolution and oxidation resistance of phenolic resin pyrolytic carbons were studied. The results showed that copper oxide (CuO) generated from the thermal decomposition of copper nitrate was reduced to copper (Cu) by the gas generated from the thermal decomposition of the phenolic resin. Carbon nanofibers with tapered structures were synthesized by Cu catalysis of pyrolysis gas at 500–800 °C. The catalytic pyrolysis of phenolic resin with Cu increased the graphitization degree and reduced the pore volume of the phenolic resin pyrolytic carbons. The combined action improved the oxidation resistance of phenolic resin pyrolytic carbons. [ABSTRACT FROM AUTHOR]

Transition‐metal catalyzed difunctionalization of olefins has attracted considerable attention as a method to construct carbon‐carbon and carbon‐hetero bonds. Herein, the copper‐catalyzed three‐component radical cross‐coupling of oxime esters, styrenes and AgSCF3 through a visible‐light‐promoted iminyl radical‐mediated carbon‐carbon bond cleavage strategy has been described. Utilizing low‐cost copper salt as both photosensitizers and cross‐couplers, this protocol delivers diverse target products, providing a supplementary approach for cyanoalkylation and trifluoromethylthiolation of drug molecules. [ABSTRACT FROM AUTHOR]

The direct palladium‐catalyzed C−H arylation of 1,3,4‐oxadiazoles with challenging aryl chloride substrates is promoted by the use of a specifically designed electron‐rich ferrocenyl diphosphane. This protocol employs 0.5 to 1.0 mol % catalyst loading without any additives such as copper or ammonium salts, and equally tolerates electron‐donating and electron‐withdrawing substituents on the (heteroaryl)aryl halides, as illustrated by the efficient synthesis in 86 % yield of the anti‐tubercular agent PHOXPY (2‐(5‐phenyl‐1,3,4‐oxadiazol‐2‐yl)pyrazine) by a late‐stage arylation using 2‐chloropyrazine. [ABSTRACT FROM AUTHOR]

A process for the synthesis of aryl thioglycosides from the aryl thianthrenium salts and 1‐thiosugars is achieved by copper(I)‐mediated, photoredox‐catalyzed reactions. The desired products could be obtained in 32% to 78% yield after irradiation with 34 W blue light at room temperature. Various functional groups, especially including halogen groups, were well tolerated under standard reaction conditions. This strategy differs conceptually from all previous S‐glycosylations in that thiosugar functionality could be incorporated into complex natural products or drugs at a late stage site‐selectively, which has not been shown via aryl halides and aryldiazonium salts. [ABSTRACT FROM AUTHOR]

The first assortment of achiral pentafluorosulfanylated cyclobutanes (SF5‐CBs) are now synthetically accessible through strain‐release functionalization of [1.1.0]bicyclobutanes (BCBs) using SF5Cl. Methods for both chloropentafluorosulfanylation and hydropentafluorosulfanylation of sulfone‐based BCBs are detailed herein, as well as proof‐of‐concept that the logic extends to tetrafluoro(aryl)sulfanylation, tetrafluoro(trifluoromethyl)sulfanylation, and three‐component pentafluorosulfanylation reactions. The methods presented enable isolation of both syn and anti isomers of SF5‐CBs, but we also demonstrate that this innate selectivity can be overridden in chloropentafluorosulfanylation; that is, an anti‐stereoselective variant of SF5Cl addition across sulfone‐based BCBs can be achieved by using inexpensive copper salt additives. Considering the SF5 group and CBs have been employed individually as nonclassical bioisosteres, structural aspects of these unique SF5‐CB "hybrid isosteres" were then contextualized using SC‐XRD. From a mechanistic standpoint, chloropentafluorosulfanylation ostensibly proceeds through a curious polarity mismatch addition of electrophilic SF5 radicals to the electrophilic sites of the BCBs. Upon examining carbonyl‐containing BCBs, we also observed rare instances whereby radical addition to the 1‐position of a BCB occurs. The nature of the key C(sp3)−SF5 bond formation step – among other mechanistic features of the methods we disclose – was investigated experimentally and with DFT calculations. Lastly, we demonstrate compatibility of SF5‐CBs with various downstream functionalizations. [ABSTRACT FROM AUTHOR]

The object of this work is to study the ignition performances of promising catalytically promoted amino-based green fuels to be used in combination with rocket-grade hydrogen peroxide. The main hypergolic parameter, the ignition delay time, was experimentally determined with an automated drop test setup. Additionally, the kinematic viscosity was experimentally measured, while the CEA2 software was used to determine the ideal rocket performances of the propellants. Three inorganic copper salts were selected as catalysts to be used in combination with monoethanolamine in concentrations ranging from 0.5 wt% to 20 wt%. Then, N,N-dimethylethylenediamine was introduced as part of a blend with monoethanolamine to target the high viscosity and low gravimetric specific impulse of the fuel for the pure monoethanolamine case. Due to the reduced monoethanolamine and low additive content, some formulations were observed to be characterized by gravimetric specific impulse higher than 320 s, and kinematic viscosity lower than 5 cSt while retaining ignition delay times shorter than 30 ms with 98 wt% HTP. Finally, the addition of ethanol to the blend was preliminarily investigated to improve the additive solubility. The effects on the ignition delay time were found to depend on the concentration ratio of the two amines. [ABSTRACT FROM AUTHOR]

Liquid assisted ball milling of [NHC]HBr (NHC = N-heterocyclic carbene) salts with copper(I) chloride, and a range of alkali metal complexes was shown to efficiently produce (NHC)CuX (NHC = normal or RE-NHC, X = halide, alkoxide, amide, alkyl, aryl; RE-NHC = ring-expanded NHC). [ABSTRACT FROM AUTHOR]

This research utilized a recently developed co-melting crystallization method to synthesize four distinct energetic coordination compounds (ECCs). The method involves the direct heating of organic ligands with inorganic salts, leading to the formation of the desired ECCs upon cooling and subsequent crystallization. This approach effectively bypasses various challenges associated with the conventional solvent-based ECC preparation process. In this study, the organic ligands employed were pyrazole and 4-chloropyrazole, while the inorganic salts included copper nitrate and copper perchlorate. A rigorous pre-experiment was meticulously designed to validate the feasibility of this method, followed by control experiments to underscore its advantages. Subsequently, comprehensive characterizations were conducted on the four ECCs, with a primary emphasis on their crystal structures and energetic properties. Notably, ECCs-3 and ECCs-4, among the synthesized ECCs, exhibit significant potential for applications in pyrotechnic materials and ignition agents. This work extends the practical applicability of the co-melting crystallization method we have developed, providing further substantiation of its advantages and potential. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview and evaluation of the studies conducted over the past 15 years into copper catalyzed reactions for C(sp2)−C(sp2) bond formation via C(sp2)−H activation. The investigations encompass a wide array of starting materials and substrates. The range of substrates studied has been broadened to encompass C−H activation of aryls, heteroaryls, and alkenyl groups. Furthermore, in some cases only catalytic amounts of copper salts were required to drive the challenging C−H functionalization, indicating a promising avenue for future research. [ABSTRACT FROM AUTHOR]

Implementation of new activated carboxylic acids is crucial to switch reversibly chemical systems over time in a safer manner. By applying cheap 1,3‐acetonedicarboxylic acid, the pH of aqueous solutions can be decreased before autonomously evolving over time back again to a higher value upon diacid decarboxylation. This decarboxylation can be catalysed by different species such as simple amines or simple metals such as iron and copper salts. This process generates 2 molecules of CO2 and acetone as single waste, considerably decreasing the toxicity associated with such activated acids. The potential of this weak diacid was confirmed by reversibly disrupting a strong gel upon diacid addition and opens the way to the application in complex chemically fuelled systems. [ABSTRACT FROM AUTHOR]

An efficient and unprecedented cross‐coupling between acylzirconocenes, readily available starting materials conveniently prepared by hydrozirconation of alkenes and a subsequent carbonylation with carbon monoxide, and diaryliodonium tetrafluoroborates is reported. This procedure enables the synthesis of a broad variety of alkyl‐aryl‐ketones upon simple catalysis with copper cyanide without the need of additional ligands and only requires a low pressure of carbon monoxide generated in situ, in a two‐chamber reactor, from N‐formylsaccharin. [ABSTRACT FROM AUTHOR]

The article discusses the aspects of obtaining red-colored phosphate coatings on the surface of steel at low temperatures. The solution for color phosphating is based on a modified composition based on the chemical «Majef» with sodium nitrite as an accelerator, organic additives of glycerin and Trilon B to improve the quality of precipitated phosphate coatings, and the preparation of OS-20 for emulsifying and wetting the surface. To precipitate red phosphate coatings, it is proposed to introduce copper salt into the composition of the phosphating solution. In the phosphating solution with the addition of copper salt, contact deposition of copper occurs before the formation of a phosphate film on the surface of the steel. This copper layer stains the resulting phosphate coating but does not adhere to the steel surface. To obtain a red phosphate coating of satisfactory quality, it is recommended to first soak the steel product in a modified cold phosphating solution for 15 min, and after the formation of a thin layer of phosphate film on the surface of the steel, introduce copper salt into the solution. Red phosphate coatings are inferior in their protective abilities to unpainted phosphate films; they have greater roughness and high porosity. Although red phosphate coatings have a protective ability, their anticorrosive properties should be improved by additional varnish treatment. [ABSTRACT FROM AUTHOR]

The reaction of copper(II) chloride with (NH4)2RuNOCl5 in the presence of ammonia or ethylenediamine (en) gives [CuLn][RuNOCl5] double complex salts with a nearly quantitative yield. The structures of the reaction products are determined by single crystal X-ray diffraction. The structure of [Cu(NH3)4(H2O)2][RuNOCl5] is formed by chains of alternating isolated cations and anions. The structure of [Cu(en)2][RuNOCl5] contains polymer chains due to the coordination of bridging chloride ligands along axial coordinates of square planar [Cu(en)2]2+. The thermal analysis and powder X-ray diffraction data show that the formation of Ru–Cu solid solutions during thermolysis of the studied compounds is complicated by the release of volatile copper(I) chloride at the early stages of thermolysis. [ABSTRACT FROM AUTHOR]

A facile strategy that directly reduces alkynyl‐silver precursors and copper salts for the synthesis of bimetallic nanoclusters using the weak reducing agent Ph2SiH2 is demonstrated. Two alkynyl‐protected concentric‐shell nanoclusters, (Ph4P)2[Ag22Cu12(C≡CR)28] and (Ph4P)3[Ag42Cu12Cl(C≡CR)36] (Ag22Cu12 and Ag42Cu12Cl, R=bis(trifluoromethyl)phenyl), were successfully obtained and characterized by single‐crystal X‐ray diffraction and electro‐spray ionization mass spectrometry. For the first time, a hybrid 55‐atom two‐shell Mackay icosahedron was found in Ag42Cu12Cl, which is icosahedral M54Cl instead of M55. The incorporation of a chloride in the metal icosahedron contributes to the stability of the cluster from both electronic and geometric aspects. Alkynyl ligands show various binding‐modes including linear "RC≡C−Cu−C≡CR" staple motifs. [ABSTRACT FROM AUTHOR]

The results of studies on determination of the ignition delay time of hypergolic low-toxicity ("green") propellants with high-test hydrogen peroxide as an oxidizer are discussed. The use of liquid and solid fuels containing compounds that catalyze the hydrogen peroxide decomposition (manganese and copper salts) or actively react with hydrogen peroxide (e.g., NaBH4) allows preparation of propellants with the ignition delay time shorter than 20 ms, which allows using these propellants in liquid or hybrid rocket engines. The use of ionic liquids as a fuel in most cases also requires introducing promoters. [ABSTRACT FROM AUTHOR]

A primary amine, salicylaldehyde and copper salt were combined to prepare the bis(N-benzyl-salicydenaminato)copper (II) complex. The copper (II) complex was then used as a precursor to synthesize mixed phase morphological copper oxide nanoparticles via thermal decomposition method using trioctylphosphine oxide as a capping molecule at different temperatures of 120, 180, and 240 °C. The XRD patterns of copper oxide nanoparticles synthesized at lower temperatures exhibit a mixture of monoclinic structure of CuO whereas the nanoparticles synthesized at higher temperature reveals the peaks that are attributed to mainly face-centered-cubic metallic Cu. The TEM images showed spherical particles that were increasing in sizes when the temperature was raised. [ABSTRACT FROM AUTHOR]

A versatile catalytic platform consisting of pyridine‐containing oxalamide and copper salt was developed. The resulting complexes were fully characterized by spectroscopic analyses, showing a successful complexation of copper metal. The applicability of the newly prepared platforms was evaluated in a one‐pot three‐components system for the preparation of 1,4‐disubstituted 1,2,3‐triazole via 1,3‐dipolar cycloaddition of terminal acetylenes, benzyl surrogates, and sodium azide in an aqueous environment. The corresponding cyclization proceeded smoothly affording the expected triazole products in moderate to good yields. In addition, the transformation of arylboronic acids to the corresponding phenols via ipso‐hydroxylation was also explored using the same platform in an aqueous basic condition. In the course of the study, unfortunately, some drawbacks that could limit the applicability of the catalytic platform were also observed especially in terms of recyclability of the platforms. [ABSTRACT FROM AUTHOR]

An efficient and versatile copper- or iron-catalyzed direct β-C(sp2)–H methylation of enamides by using dicumyl peroxide (DCP) as the methylating reagent has been developed. This methodology provides convenient access to a wide range of β-C(sp2)-methylated enamides with exclusive E-selective control in moderate to good yields. Mechanistic studies reveal that a methyl radical was involved in this transformation. Notably, this method features cheap copper or iron salts as the catalyst, a simple procedure, commercially available methylation reagents, a broad substrate scope, and excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

Isocoumarins and dihydroisocoumarins are important skeletons with a wide range of biological activities, such as anti-bacterial, anti-allergy, anti-fungal, anti-tumor, and anti-HIV properties. Herein, we demonstrated divergent syntheses of isocoumarins and 3,4-dihydroisocoumarins by intramolecular dehydrogenative cyclization of 2-(3-oxobutyl) benzoic acids. This transformation undergoes Csp3–H bonds and O–H bonds coupling in air using copper salt. The reactions may undergo free radical process. [ABSTRACT FROM AUTHOR]

In this study, we present solid state processes for the fabrication of copper nanoclusters (NCs) and hierarchical supraparticles (SPs). To achieve this, copper salt and thiols are mixed and are then grinded for 10–15 min, and the nano-products are thereby obtained. Interestingly, it was found in this study that the formation of the NCs or SPs is completely dependent on the grinding methods that are used: with mechanical grinding, the products are several nanometer-sized NCs, whereas manual grinding in an agate mortar can obtain Cu SPs with diameters as low as 10 nm all the way up to 200 nm. The photoluminescence emission wavelength of the nano-products is located at ~680 nm. The Stokes shift of the obtained nanomaterials is more than 300 nm. The emission quantum yields of the Cu NCs and SPs are as high as 47.5% and 63%, respectively. Due to their facile fabrication processes and their favorable optical properties, the two as-prepared types of copper nano-materials exhibit great potential for bio-imaging and bio-sensing applications. [ABSTRACT FROM AUTHOR]

Different coordination polymers that are prepared by using various copper salts with diverse counter ions (perchlorate/ nitrate/ acetate/ iodide) along with bis(4‐nitrophenyl)phosphoric acid (BNPP) and 4,4′‐bipyridine (bpy) have been reported. In each case, two distinct coloured crystals (royal and cyan blue) are observed, concomitantly. The composition and structural features of royal blue crystals are the same in all structures irrespective of counter ions employed, yielding a distorted square pyramid structure with each copper metal ion coordinated to one BNPP and four bpy molecules along with six water molecules in the lattice. However, the compositions of the cyan blue crystals are different depending on the counter ions used. Thus, copper metal ion was found in distinct coordination spheres in each structure. For example, perchlorate anion produces a mixed geometry structure {[Cu(BNPP)2(bpy)2(H2O)][Cu(bpy)2(H2O)2]}ClO4 containing two Cu(II) metal ions with independent square pyramid and square planar geometries along with an uncoordinated perchlorate anion. In addition, it also gives a structure with a molecular formula [Cu2(BNPP)5(bpy)3], devoid of perchlorate ions, having two different Cu(II) coordination spheres (square pyramid and square planar), which are connected together. In contrast, with nitrate ions, cyan blue crystals form a square pyramidal geometry with the formula [Cu(BNPP)2(bpy)2(NO3)], in which the anion is coordinated to Cu(II) ions. Furthermore, with acetate ion, two different complexes having formulae [Cu(BNPP)2(bpy)2] ⋅ 2H2O and [Cu(bpy)2(acetate)2](H2O)2(nitrophenol) are observed, with the latter complex is formed possibly due to the facile hydrolysis of BNPP molecules yielding a nitrophenol. In both the complexes Cu(II) projects a square planar geometry. However, in the case of iodide anion, a complex [Cu2(BNPP)5(bpy)3] ⋅ 2H2O is formed, without any anion, in which two distinct Cu metal ions with tetra‐ and penta‐coordinated spheres are connected together through bpy molecules and yield square planar and square pyramid geometries. The structures of these coordination polymers are thoroughly characterised by single crystal X‐ray diffraction and spectroscopic methods (IR, solid state UV and photoluminescence). [ABSTRACT FROM AUTHOR]

Three types of CuO with different micro–structures were applied to catalyze the conversion of glycerol to lactic acid. The structure–activity relationship between CuO and its catalytic performance was investigated by combining experiments and theoretical calculations. We demonstrated that two CuO samples (CuO–BCC and CuO–CA), as prepared by calcining copper salts, show larger lattice spacing than that of commercial CuO (CuO–COM). In the catalytic experiments, CuO–BCC, which had the largest lattice spacing (d = 0.2480 nm), exhibited the highest yield of 78.54% for lactic acid. The lattice strain caused by lattice expansion was considered more favorable for CuO–BCC in adsorbing glycerol molecules, thereby improving the conversion of glycerol to lactic acid. The DFT simulation calculation results further prove that CuO–BCC has a larger adsorption energy for glycerol and a smaller thermodynamic energy barrier for the dehydrogenation of glycerol to form the key intermediate products (glyceraldehyde and 1,3-dihydroxyacetone) than CuO–COM. This study demonstrates the role of lattice strain effects in the development of catalysts and provides ideas for catalytic glycerol-selective oxidation studies. [ABSTRACT FROM AUTHOR]

A direct C−H bond oxidative sulfonylation of β‐alkyl cyanoalkenes with sodium sulfinates was reported. This transformation involves the use of a copper salt catalyst, along with a catalytic amount of I2 and DMSO as the oxidative system, which provides a straightforward and practical access to various cyanoallyllic sulfones. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The proposed article relates to synthesis and the study of new propargyl ester derivatives, and biostimulation activity of 4-(bis(2- hydroxyethyl)amino)but-2-yn-1-yl butyrate. Aminomethylation reactions of the obtained propargyl ester with ethanolamine and paraform were carried out in the presence of a catalyst. Copper salts were used as a catalyst. The structure of the new propargyl ester derivatives was established by IR and ¹H-, 13C- NMR spectroscopy. Comparative tests show that the test derivative of the drug 4-(bis(2- hydroxyethyl)amino)but-2-yn-1-yl butyrate showed a higher growth-promoting activity. [ABSTRACT FROM AUTHOR]

Conjugated diyne derivatives are important scaffolds in modern organic synthetic chemistry. Using the Glaser reaction involves the coupling of terminal alkynes which can efficiently produce conjugated diyne derivatives, while the use of a stoichiometric amount of copper salts, strong inorganic base, and excess oxidants is generally needed. Developing an environmentally friendly and effective method for the construction of symmetrical 1,3-diynes compounds by Glaser coupling is still highly desirable. In this study, we present an economical method for the production of symmetric diynes starting from various terminal acetylenes in a Glaser reaction. A simple and practical bis-N-heterocyclic carbene ligand has been introduced as efficient ligands for the Cu-catalyzed Glaser reaction. High product yields were obtained at 100 °C for a variety of substrates including aliphatic and aromatic terminal alkynes and differently substituted terminal alkynes including the highly sterically hindered substrate 2-methoxy ethynylbenzene or 2-trifluoromethyl ethynylbenzene and a series of functional groups, such as trifluoromethyl group, ester group, carboxyl group, and nitrile group. The established protocol is carried out in air under base-free condition and is operationally simple. These research work suggest that bis-N-heterocyclic carbene could also an appealing ligand for Glaser reaction and provide a reference for the preparation of symmetric 1,3-diynes in industrial filed. [ABSTRACT FROM AUTHOR]

Modification of the resorcin[4]arenes 1a/1b and the methylresorcin[4]arene 1c by phosphorylation, oxidation, hydrolysis and acidification led to isolation of three new tetraphosphate cavitands 3a–3c. Interactions of the tetraphosphate cavitands 3a–3c with CuCl or CuBr in pyridine afforded three multi-component compounds (3a–H)·[CuCl(py)4]·8H2O (A, py = pyridine) and (3b–3H)·[CuX(py)4]·[Cu(py)3(H2O)3]·nH2O (B, X = Cl, n = 5.6; C, X = Br, n = 5). The molecular structures of 3c·29.2H2O, {3cNa}Cl·7.2H2O, A, B and C have been determined by X-ray diffraction studies. The coordinative and H-bonding interactions of sodium and copper salts with the phosphate groups were presented in {3cNa}Cl·7.2H2O and B/C, respectively, making them dimensional supramolecular entities. [ABSTRACT FROM AUTHOR]

The influence of plasma-reduction treatment on iron and copper compounds at different oxidation states was investigated in this study. For this purpose, reduction experiments were carried out with artificially generated patina on metal sheets and with metal salt crystals of iron(II) sulfate (FeSO4), iron(III) chloride (FeCl3), and copper(II) chloride (CuCl2), as well as with the metal salt thin films of these compounds. All the experiments were carried out under cold low-pressure microwave plasma conditions; the main focus was on plasma reduction at a low pressure in order to evaluate an implementable process in a parylene-coating device. Usually, plasma is used within the parylene-coating process as a supporting tool for adhesion improvement and micro-cleaning efforts. This article offers another useful application for implementing plasma treatment as a reactive medium in order to apply different functionalities by an alteration in the oxidation state. The effect of microwave plasmas on metal surfaces and metal composite materials has been widely studied. In contrast, this work deals with metal salt surfaces generated from a solution and the influence of microwave plasma on metal chlorides and sulfates. While the plasma reduction of metal compounds commonly succeeds with hydrogen-containing plasmas at high temperatures, this study shows a new reduction process that reduces iron salts at temperatures between 30 and 50 °C. A novelty of this study is the alteration in the redox state of the base and noble metal materials within a parylene-coating device with the help of an implemented microwave generator. Another novelty of this study is treating metal salt thin layers for reduction purposes in order to provide the opportunity to include subsequent coating experiments to create parylene metal multilayers. Another new aspect of this study is the adapted reduction process of thin metal salt layers consisting of either noble or base metals, with an air plasma pre-treatment prior to the hydrogen-containing plasma-reduction procedure. [ABSTRACT FROM AUTHOR]

A mild and efficient copper‐mediated trifluoromethylation of diaryliodonium salts with readily available fluoroform has been developed. The reaction exhibits excellent functional group tolerance, affording trifluoromethylated arenes in good yields. This approach provides a straightforward incorporation of CF3 group into complex molecules for drug discovery. [ABSTRACT FROM AUTHOR]

We developed an alkynylation of allylic phosphates with acetylenes in the presence of copper and magnesium salts. The reaction proceeded regioselectively to afford the corresponding 1,4‐enynes. Furthermore, the functional group tolerance of this reaction was established. As an application, the 1,4‐enyne intermediate involved in the synthesis of 13R,19S,20S‐trihydroxydocosapentaenoic acid could be efficiently synthesized. [ABSTRACT FROM AUTHOR]

The selective detection of hydrogen sulfide (H2S) is an important task because of its potentially hazardous effects not only on the environment but also on human health. Here, we present the zirconium‐based MOF‐808, which was modified with copper salts, as a colorimetric sensor material for the visible, reversible and sensitive H2S detection at room temperature. The copper cations, which are incorporated in the oxidation state +II, are installed at the inorganic building units (IBUs) of the framework so that they are accessible for interactions with H2S. The activated copper doped MOF‐808 powder shows significant and fast color change in the presence of H2S, which can be detected by UV‐vis spectroscopy. Moreover, the detection process is reversible by heating the material to 120 °C under ambient conditions leading to its decolorization. The detection performance of the material was studied by in situ UV‐vis measurements in a reaction chamber. The material was able to respond to 100 ppm H2S in several cycles of exposure and heating to 120 °C under moist air conditions in a defined wavelength range. This reversibility is very uncommon for copper‐based H2S sensing reactions and highlights the potential of MOFs as selective sensing materials. [ABSTRACT FROM AUTHOR]

Octadecylazanediyl dipropionic acid (C18ADPA) is a zwitterionic amphiphile with a dendritic headgroup. C18ADPA self-assembles to lamellar networks, which encompasses water and forms a low-molecular-weight hydrogel (LMWG). In this study, we use the C18ADPA hydrogel as a drug carrier for the in vivo delivery of a copper salt for wound healing in a mouse model. A structural transition was observed based on cryo-scanning electron microscope (cryo-SEM) images after drug loading. The C18ADPA hydrogel, which had a layered structure, transformed into a self-assembled fibrillar network (SAFiN). The mechanical strength of the LMWG has always been an important issue in its applications. However, due to the structural transition, both the storage and loss moduli increased. In vivo tests showed that wound closure was faster after applying the hydrogel formulation compared with the Vaseline formulation. For the first time, we have also provided histological evidence of these effects on skin tissue. The hydrogel formulation exhibited clear advantages in regenerating tissue structure over traditional delivery formulations. [ABSTRACT FROM AUTHOR]

The reaction of octakis(3-chloropropyl)octasilsesquioxane with four equivalents of 1-hexylimidazole or 1-decylimidazole gave two products labelled as HQ-POSS (hexyl-imidazolium quaternized POSS) and DQ-POSS (decyl-imidazolium quaternized POSS) as regioisomer mixtures. An investigation of the biological activity of these two compounds revealed the higher antimicrobial performances of HQ-POSS against Gram-positive and Gram-negative microorganisms, proving its broad-spectrum activity. Due to its very viscous nature, HQ-POSS was adsorbed in variable amounts on the surface of biologically active oxides to gain advantages regarding the expendability of such formulations from an applicative perspective. Titania and 5 wt% Cu on titania were used as supports. The materials 10HQ-POSS/Ti and 15HQ-POSS/5CuTi strongly inhibited the ability of Pseudomonas PS27 cells—a bacterial strain described for its ability to handle very toxic organic solvents and perfluorinated compounds—to grow as planktonic cells. Moreover, the best formulations (i.e., 10HQ-POSS/Ti and 15HQ-POSS/5CuTi) could prevent Pseudomonas PS27 biofilm formation at a certain concentration (250 μg mL−1) which greatly impaired bacterial planktonic growth. Specifically, 15HQ-POSS/5CuTi completely impaired cell adhesion, thus successfully prejudicing biofilm formation and proving its suitability as a potential antifouling agent. Considering that most studies deal with quaternary ammonium salts (QASs) with long alkyl chains (>10 carbon atoms), the results reported here on hexylimidazolium-based POSS further deepen the knowledge of QAS formulations which can be used as antifouling compounds. [ABSTRACT FROM AUTHOR]

Predictive catalysis was applied to the reaction of pyridinium 1,4‐zwitterionic thiolates with a copper carbene. Theoretical calculations were first performed to determine the suitability of their annulation reaction and to make predictions about the performance of different copper salts, diazo species, and pyridinium derivatives. With calculations in hand, the experimental conditions were optimized, the scope of the reaction was assessed, and the precision of the predictions was evaluated. Yields up to 90% were obtained for the synthesis of indolizine scaffolds in the reactivity of pyridinium 1,4‐zwitterionic thiolates with a metal carbene. [ABSTRACT FROM AUTHOR]

[Display omitted] • A concentration-dependent curve was determined using in vitro assays. • Copper chloride, copper sulfate, and nitroxynil were effective against nematodes. • A synergic effect was observed against Haemonchus spp. and Trichostrongylus spp. • Copper chloride had a better effect, even in combination, against nematode parasites. Infections caused by Haemonchus spp. and Trichostrongylus spp. are major health problems for sheep and cattle. The objective of this study was to determine the efficacy of copper chloride (CuCl 2), and copper sulphate (CuSO 4) at 2.0, 7.0, 30.0, 125.0, 500.0, and 2000.0 µM formulations, and nitroxynil 34% (NTX) at 0.235 mM against gastrointestinal nematodes (GINs) of ruminants. Hence, the in vitro egg hatch test (EHT), the larval development test (LDT), and the larval migration inhibition test (LMIT) were used. Haemonchus spp. (52%) and Trichostrongylus spp. (38%) were the most frequently found parasites. The data fitted a concentration-dependent shape with the highest efficacies of CuCl 2 and CuSO 4 at 95.2 and 97.3% for parasites collected from sheep, and 95.8 and 93.4% from cattle, respectively. The combination of the 50% inhibitory concentration (IC 50) of CuCl 2 and CuSO 4 and the IC 10 of NTX showed up to a 52% increase in efficacy above the expected additive results, demonstrating a synergic/drug enhancer interaction. NTX may retain Cu-II ions by complexation, in a hitchhiking mechanism carrying the salts across the parasite cell wall, causing oxidative stress as a consequence of free radical production and cell damage. Synergy data between NTX and CuCl 2 , and CuSO 4 represent a viable opportunity to develop new formulations for combating parasites of ruminants (i.e., Fasciola hepatica , Haemonchus spp., and Oesophagostomum spp.). [ABSTRACT FROM AUTHOR]

Lithium-rich silicides (Li15Si4), formed during the electrochemical lithiation of silicon, show high reactivity with electrolyte components that contribute to capacity decay, formal lithium loss, and low coulombic efficiency. Recently, the reactivity of lithium silicides was found to be suppressed by substituting a multivalent cation (i.e. Mg, Ca) for lithium that results in the room temperature formation of a ternary Li-M-Si phase. In this study, we explored a range of multivalent electrolyte salt additives (M = Ni, Cu, La, Ce, Sr, Ba, and Ca-Mg mixed salt) in a lithium-ion cell configuration and identified a room temperature electrochemical route to the formation of new ternary and quaternary lithium silicides. Using this method, both nickel and copper salts were found to plate onto the silicon electrode surface upon lithiation. Based on refined synchrotron XRD data, multivalent cations with an ionic radius similar to Na (~1.03 Å) or smaller can be inserted electrochemically into a formally cation-deficient Li15Si4 host lattice to form new ternary (or quartenary) phases. The electrochemical synthesis of a new quaternary Li-M-M'-Si phase represents a facile route to preparing and scaling materials isostructural to the Heusler phase and electron-precise Li14MgSi4 phase that results in enhanced cycling and calendar life performance. [ABSTRACT FROM AUTHOR]

The 1,2,3-triazoles are an important class of organic compounds that are found in a variety of biologically active compounds. The most usual and efficient methodology to synthetize these compounds is the Copper-catalyzed Azide–Alkyne Cycloaddition (CuAAC), preferably by use of click chemistry principles. Therefore, the development of simple, robust, easily accessible and efficient materials as catalysts for this kind of reaction is highly desirable. In this sense, layered hydroxide salts (LHS) emerge as an interesting alternative for the click reaction. Thus, we describe herein the preparation and characterization of copper (II) layered hydroxide salts and their application as catalysts for the CuAAC reaction under solvent-free conditions. This synthetic methodology of CuAAC reaction is attractive as it follows several concepts of green chemistry, such as being easy to perform, allowing purification without chromatographic column, the process forming no sub-products, affording the desired 1,2,3-traizoles in the specific 1,4-disubstituted position in high yield, and having a short reaction time. Moreover, the photocatalysis for the degradation of methyl orange was also highly efficient using the same catalyst. [ABSTRACT FROM AUTHOR]

Crude tall oil (CTO), a side product of sulphate pulping, has promising results in moisture and decay resistance. This article reports the Pilodyn indentation hardness, basic density, and mechanical performance of 600-mm long Scots pine posts after a nine-year soil contact test. The material consisted of round and square-shaped CTO-impregnated posts, supplemented by copper salt-impregnated and untreated reference posts. In total, 240 posts were installed in fertile soil in south-eastern Finland in spring 2010. Posts were harvested in May 2019. At the end of the test, 192 posts were in a condition that allowed the preparation of specimens for density and compression tests. Discs were sawn from the ground level, as well as above and below the ground level to measure the density and deformation under static 45,000 N parallel-to-the-grain compression load. Altogether 80% of the untreated control posts were rejected from further tests due to severe decay. Square-shaped control posts had a slightly higher survival rate than the round ones. After a nine-year soil contact, the performance of CTO impregnated. Scots pine posts were clearly better than that of untreated control posts and comparable to that of copper salt-impregnated posts. The study suggests that CTO has a high potential as a non-biocide wood preservative even in structures in soil contact. [ABSTRACT FROM AUTHOR]

Bamboo is prone to mould infection and discolouration. Traditional methods of preventing mould are to peel off the green and yellow layers, and then anti-mould treatment was performed. Though these methods were efficient, the original green colour of bamboo was removed and resulted in resources waste because of the removal of the green portions. This paper presented an anti-mould property method of Moso bamboo surface by using a green colour preservation process. The results revealed that the outer bamboo skin processed a certain anti-mould effect. Based on this result, the green colour preservation method involving the alkali solution and the copper salt solution treatment processes could improve the anti-mould property of the Moso bamboo surface as well as the green colour by removing the covering wax and opening the stoma. Compared with the control, the treated specimen's mould growth was delayed by 11 days. The mould area was reduced by half, which exhibited a green colour with a low a* value of −14.91. [ABSTRACT FROM AUTHOR]

We herein report a method for divergent copper salt controlled reactions of donor‐acceptor cyclopropanes and N‐fluorobenzene sulfonimide (NFSI). Specifically, in the presence of CuX2 (X=Cl, Br), the cyclopropanes underwent formal umpolung 1,3‐aminohalogenation bifunctionalization via a free radical mediated ring‐opening process to afford 1,3‐aminochlorination and 1,3‐aminobromination products in moderate to good yields. In addition, by using CuI as a catalyst, we synthesized various aminoindane derivatives via 1,3‐aminoarylation cyclization of D‐A cyclopropanes, the reactions involved a free radical mediated ring‐opening and subsequent ring expansion via C−H bond activation. [ABSTRACT FROM AUTHOR]

Herein, new substituted ligands based on pyrazole (L1–L4) were synthesized via a one-step by condensing (1H-pyrazole-1-yl) methanol with different primary amine compounds. The present work utilized the catalytic properties of the in situ complexes formed by these ligands with various copper (II) salts viz. Cu(CH3COO)2, CuSO4, CuCl2, and Cu(NO3)2 for the oxidation of catechol to o-quinone. The studies showed that the catalytic activities depend on the nature and concentration of the ligand, the nature of the counterion, and the solvent. It was observed that the complex formed by L2 and Cu(CH3COO)2 exhibited good catalytic activity in methanol with Vmax of 41.67 µmol L−1 min−1 and Km of 0.02 mol L−1. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this manuscript, we report a radical type ring‐opening of sulfonium salts with heteroarenes under visible light conditions. This developed method does not require noble metal photocatalysts, or stoichiometric amount of external oxidants, and has a application prospect in the synthesis of organosulfur compounds and bioactive molecules. This radical type ring‐opening photocatalytic system could inspire further applications of sulfonium salts in C(sp3)−C(sp2) bond forming reactions. [ABSTRACT FROM AUTHOR]

In the presence of CuOAc, a series of unsymmetric ureas can be generated in moderate to good yields under mild reaction conditions (10 mol% of CuOAc, 2 equiv t-BuONa or PhONa, 30 °C), using aryl isocyanides and O-benzoyl hydroxylamines as the readily accessible starting materials. The reactions might undergo a cascade process involving isocyanide insertion into the N-O bond and Mumm-type rearrangement. This work represents a rare example of isocyanide insertion into N-O bonds, which would extend isocyanide insertion chemistry. [ABSTRACT FROM AUTHOR]

This report focuses on a facile and one-pot way to synthesize stable Cu nanoparticles (NPs) through a bacterial approach using an inexpensive and non-toxic copper salt in the aqueous solution. Copper NPs were obtained from an extracellular enzymatic metal-reduction process via bacterial strains PN14F and B3 which were similar with Bacillus haynesii (99.87%) and Bacillus halotolerans (100%), respectively, on the basis of phylogenic analysis. It was found that Cu NPs were formed in the cell-free culture liquid but not in the fresh biomass medium, so that it was hypothesized that an extracellular compound was responsible for the proceeding. According to the spectroscopic data, the NPs can bind to the proteins through their free amine or carboxylate groups. It is noteworthy that by varying the bacterial supernatant, the remarkable changes occur in the size and morphology of copper NPs, where their thickness and diameter are observed to be 2–30 and 1–15 nm in the presence of bacterial strains PN14F and B3, respectively. It is noticeable that this manner is a novel, green, eco-friendly and suitable method for large-scale production. Finally, the as-made Cu NPs showed antibacterial activity against B. Subtilis, in which a significant decrease was observed in its growth. [ABSTRACT FROM AUTHOR]

A convenient and efficient one-pot procedure for the synthesis of pyrano[3,2-c]chromenes has been developed via three-component condensation of 4-hydroxycoumarin, aromatic aldehydes, and malononitrile in the presence of a catalytic amount of nano-titanium oxide doped with aluminum and copper salts (Al@Cu@TiO2) as a novel nanocatalyst. The catalyst was prepared via the reaction of titanium(IV) isopropoxide, Al(NO3)3, and Cu(NO3)2 in aqueous methanol. The proposed protocol offers various advantages such as shorter reaction times, use of a heterogeneous catalyst, and high yield of products in combination with simple experimental and workup procedures. The catalyst can be recovered and reused for at least five runs without any significant impact on the yields. [ABSTRACT FROM AUTHOR]

Background. The aim of the study was to find out the influence of excess copper and zinc ions in drinking water on the bile-forming and bile-secreting functions of the liver in the conditions of mechanical trauma and the effectiveness of the antidote therapy. Material and methods. The experiments were performed on 60 Wistar strain male rats weighing 180-200 g. There were 3 groups of experimental animals in the experiment: 1 group - only skeletal trauma was simulated; 2 group - a skeletal injury was simulated and zinc and copper salts were administered; 3 group - skeletal trauma + zinc and copper salts followed by Unithiol treatment. Results. In the late period of traumatic illness (14-28 days), after a severe skeletal injury, the intensity of bromsulfalein increased in the liver tissue, and there were signs of increased formation of direct bilirubin in terms of additional intake of copper and zinc ions. The animals with severe skeletal trauma were accompanied by a significant deterioration in the functional state of the liver in comparison to the animals with similar skeletal trauma without additional intoxication. Conclusions. Under conditions of additional intake of copper and zinc ions (in the 2nd group), after 14 days and 28 days of observation, all the studied indicators are much higher than in the group of the animals without additional intoxication with these ions. The use of Unithiol reduced the toxic effect of copper and zinc ions on the studied indicators of the functional state of the liver both in the early and late period of the traumatic disease. [ABSTRACT FROM AUTHOR]