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Edible bivalves constitute an important bioresource from an economic point of view, and studies on their immune responses to environmental pollutants are crucial for both the preservation of biodiversity and economic reasons. The worldwide diffusion of copper(I)-based antifouling paints has increased copper leaching into coastal environments and its potential impact on both target and nontarget organisms. In this study, immunotoxicity assays were carried out with short-term (60 min) cultures of hemocytes from the bivalves Mytilus galloprovincialis--a mussel dominant in the macrofouling community--and Ruditapes philippinarum--a clam dominant in the soft-sediment community--exposed to CuCl to compare the toxic effects on their immune responses. The LC50 values were similar, 40 μM (3.94 mg L-1) for the mussel and 44 μM (4.33 mg L-1) for the clam. In both species, apoptosis occurred after exposure to 1 µM (98.9 μg L-1) CuCl, the concentration able to significantly increase the intracellular Ca2+ content. Biomarkers of cell morphology and motility revealed microfilament disruption, a significant decrease in yeast phagocytosis and lysosome hydrolase (β-glucuronidase) inhibition beginning from 0.5 µM (49.5 μg L-1) CuCl in both the mussel and clam. The same concentration of CuCl affected biomarkers of oxidative stress, as a significant decrease in reduced glutathione content in the cytoplasm and inhibition of mitochondrial cytochrome-c oxidase (COX) were detected in both species. Comparison of the biomarkers showed that clam is more sensitive than the mussel regarding alterations to the lysosomal membrane and reactive oxygen species (ROS) production, which supports the potential harmful effects of antifouling biocides on the survival of nontarget pivotal species in the coastal community. [ABSTRACT FROM AUTHOR]

Edible bivalves constitute an important bioresource from an economic point of view, and studies on their immune responses to environmental pollutants are crucial for both the preservation of biodiversity and economic reasons. The worldwide diffusion of copper(I)-based antifouling paints has increased copper leaching into coastal environments and its potential impact on both target and nontarget organisms. In this study, immunotoxicity assays were carried out with short-term (60 min) cultures of hemocytes from the bivalves Mytilus galloprovincialis—a mussel dominant in the macrofouling community—and Ruditapes philippinarum—a clam dominant in the soft-sediment community—exposed to CuCl to compare the toxic effects on their immune responses. The LC50 values were similar, 40 μM (3.94 mg L-1) for the mussel and 44 μM (4.33 mg L-1) for the clam. In both species, apoptosis occurred after exposure to 1 µM (98.9 μg L-1) CuCl, the concentration able to significantly increase the intracellular Ca2+ content. Biomarkers of cell morphology and motility revealed microfilament disruption, a significant decrease in yeast phagocytosis and lysosome hydrolase (β-glucuronidase) inhibition beginning from 0.5 µM (49.5 μg L-1) CuCl in both the mussel and clam. The same concentration of CuCl affected biomarkers of oxidative stress, as a significant decrease in reduced glutathione content in the cytoplasm and inhibition of mitochondrial cytochrome-c oxidase (COX) were detected in both species. Comparison of the biomarkers showed that clam is more sensitive than the mussel regarding alterations to the lysosomal membrane and reactive oxygen species (ROS) production, which supports the potential harmful effects of antifouling biocides on the survival of nontarget pivotal species in the coastal community.

We have developed a facile and sustainable method to produce a novel θ-Al2O3-supported CuCl adsorbent through impregnation methods using CuCl2 as the precursor. In an easy two-step process, θ-Al2O3 was impregnated with a known concentration of CuCl2 solutions, and the precursor was calcined to prepare CuCl oversupport. The developed novel θ-Al2O3-supported CuCl adsorbent was compared with an adsorbent prepared through the conventional method using CuCl salt. The adsorbents were characterized via X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and temperature-programmed reduction (H2-TPR). Overall, the adsorbent indicates a high CO adsorption capacity, high CO/CO2 and CO/N2 selectivity, and remarkable reusability performance. This process is operated at ambient temperature, which minimizes operation costs in CO separation processes. In addition, these results indicate that the systematic evaluation of alumina-supported CuCl adsorbent can provide significant insight for designing a realistic PSA process for selective CO separation processes. [ABSTRACT FROM AUTHOR]

This study describes the synthesis and characterization of Cu-doped ZnO nanorods (NRs) by an electrochemical method in the presence of two different Cu precursor (Cu+2 and Cu+) in order to improve photocurrent generation. Analyses of the resulting materials by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–Vis and electrochemical photocurrent (ECP) spectroscopy confirm the formation of well-aligned ZnO Würtzite nanostructures in the form of hexagonal rods. For both doping source with a concentration of up to 0.5%, the following changes were observed: a distortion of the ZnO morphology, an increase in transmittance to 96% for ZnO doped with Cu+2, and a reduction of the energy gap from 3.36 eV to 3.06 and 3.02 eV for ZnO doped with Cu+2 and Cu+, respectively. From photoelectrochemical tests, the photo-current density was improved up to 0.05 mA cm-2 in the presence of Cu doping, which is twelve times superior to that of undoped ZnO nanorods, which means that the incorporation of Cu+2 or Cu + significantly improves the separation efficiency of photogenerated electron-hole pairs. These results can be considered promising for optoelectronic and photocatalysis applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Copper(I) and silver(I) chloride complexes containing triphenylphosphine (PPh3) and 4-phenyl-thiosemicarbazide (4-PTSC) ligands were prepared and structurally analyzed, namely [CuCl(4-PTSC)(PPh3)2] (1) and [AgCl(4-PTSC)(PPh3)2]Ch3CN (2). Both compounds (1) and (2) exhibit a distorted tetrahedral metal coordination environment with two P atoms from two PPh3 ligands, one terminal S atom from the 4-PTSC ligand and a chloride ion. Intramolecular N-H···Cl and N-H···N hydrogen bonds are observed (graph set motifs S(6) and S(5), respectively). In the crystals of both complexes, molecules are linked to form dimers via bifurcated N-H···Cl hydrogen bonds involving the amine and chloride units. For compound (2), a solvate acetonitrile molecule acts as a hydrogen bond donor and acceptor via C-H(Ch3CN)···Cl and C-H···N(Ch3CN) interactions, leading to the formation of 1D chains along [010]. [ABSTRACT FROM AUTHOR]

The reaction of In(C6F5)3·Et2O with NHCdipp·CuCl and NHCdipp·AgCl in dichloromethane at room temperature leads to the formation of the complex [(NHCdipp)Cu(μ-Cl)2In(C6F5)2] and the solvate [(NHCdipp)2Ag]+· [In2(μ-Cl)(C6F5)6]–·СH2Cl2 [NHCdipp—N,N′-bis(isopropylphenyl)imidazol-2-ylidene]. Structures of the obtained compounds were determined by the single crystal X-ray diffraction analysis. An increase in Lewis acidity due to the introduction of electronegative C6F5 groups makes it possible to stabilize the binuclear anion [In2(μ-Cl)(C6F5)6]–. [ABSTRACT FROM AUTHOR]

An ef cient synthesis of diazaalkatetraynes and tetraaza macroheterocycles by the Mannich aminomethylation of α,ω-di(tetra)acetylenes with secondary diamines and aldehydes using CuCl as a catalyst was developed. [ABSTRACT FROM AUTHOR]

By virtue of the reductive coupling reactivity of samarium, cuprous chloride can effectively catalyze the homocoupling of alkylhalides, including the Csp3‐Csp3 coupling of benzyl halides and the Csp2‐Csp2 coupling of aryl halides. Under mild conditions, the homocoupling reactions of benzyl halides proceeded with excellent yields, while aryl halides and heteroaryl halides formed the coupling products in moderate yields. Only 10 mol% cuprous chloride was enough to catalyze the reaction and potassium iodide proved to be necessary. The mechanism of the catalytic process was also discussed. [ABSTRACT FROM AUTHOR]

Three new Cu(I) π-complexes with 2,5-bis(allylthio)-1,3,4-thiadizole (Bialtia) ([Cu3Cl3(Bialtia)2] (1), [Cu3Cl3(Bialtia)] (2), and [Cu2Cl2(Bialtia)] (3)) are obtained by the alternating current electrochemical synthesis and studied by single crystal X-ray diffraction. A distinctive feature of Bialtia is its ability to coordinate to Cu(I) atoms by nitrogen atoms of the thiadiazole core and two allyl groups. The formation of island inorganic {Cu3Cl3} moieties occurs in 1 through π coordination of two independent Bialtia molecules by three metal atoms. Due to the absence of one Bialtia molecule in 2, inorganic {-Cu3Cl3-} subunits join into infinite chains {[Cu3Cl3(Bialtia)]}n}. The structure of [Cu2Cl2(Bialtia)] (3) contains two Cu(I) atoms with different coordination environments: distorted tetrahedral and trigonal. [ABSTRACT FROM AUTHOR]

An unexpected sequence of forming different crystal lattices for the CuCl nanophases in potassium aluminoborate glass depending on the preceding heat treatment temperature is revealed. The hexagonal wurtzite-like nanocrystals are shown to crystallize from the liquid CuCl nanosize droplets separated at the lower heat treatment temperatures (380 °C to no more than 400 °C) than in the case for the cubic sphalerite-like CuCl nanocrystals (higher than 400 °C). This sequence is inverse with respect to the standard temperature sequence of crystallizing the bulk hexagonal and cubic phases from a melt that is known for both CuCl and its structural prototype, ZnS. A tentative explanation for the effects revealed is proposed, the explanation assuming the principal role of internal pressure in the CuCl nanodroplets in setting the location of a phase point at the phase diagram. [ABSTRACT FROM AUTHOR]

Superparamagnetic CuCl nanoparticles were prepared and identified as an effective heterogeneous catalyst for the tandem transformation of methylarenes and 1,3-dicarbonyl compounds into the corresponding enole esters by the use of tert-butyl hydroperoxide as an external oxidant. The catalyst can be removed from the reaction medium simply by use of an external magnet. As a consequence, various derivatives of enol esters were synthesized in moderate to good yields. [ABSTRACT FROM AUTHOR]

This work describes a successful copper(I)-catalyzed radical cyclization of β-haloethylallylamines bearing an unprotected NH-group while retaining catalyst-redox activity. The cyclization occurs regio- and diastereoselectively at 0 °C and furnishes diversely substituted 1,3- trans-(NH)-pyrrolidines directly in high isolated yields. An involvement of the bulky copper complex in the cyclization step as the possible reason for the diastereoselectivity was proposed. Synthetic applications of the products in the preparation of useful 4-chloro-NH-pyrrole in a single step, has also been demonstrated. A quick, mild and general method involving simple addition of trichloroacetic acid/dimethyl sulfoxide (CCl3CO2H-DMSO) solution to readily accessible N-allylaldimines and ketimines tolerating acid-sensitive and highly deactivating substituents was developed to access the amine precursors. [ABSTRACT FROM AUTHOR]

The present study on tetrazole compounds, which have a wide area of application, proposes a new, simple and highly effective method. A series of 5-substituted 1H-tetrazoles were synthesised in DMF via the [3 + 2] cycloaddition reaction, in which different aryl nitriles with sodium azide were used and copper(I) chloride served as a catalyst. Short reaction times, high yields and simple procedures rendered this method attractive and useful for the organic synthesis of 5-substituted 1H-tetrazoles. A further advantage was the use of an environmentally friendly catalyst. [ABSTRACT FROM AUTHOR]

Detailed identification and monitoring of gaseous species released during thermal decomposition of two thiourea (tu) complexes of CuCl, one of them, Cu(tu)Cl 1/2HO (1) poor, while the other, Cu(tu)Cl ( 2) rich in thiourea, have been carried out in flowing air atmosphere up to 800 °C by both coupled TG-EGA-FTIR and simultaneous TG/DTA-EGA-MS. The thermal decomposition of 1, prepared actually from CuCl, has shown evolution of similar gas mixture and dynamics by TG/DTA-MS, as had been measured with TG-FTIR and published earlier, except that no evolution of ammonia has been detected, at all. Probably, the intense co-evolution of acidic vapors (HCl and SO) has prevented NH to reach the ionization chamber of the mass spectrometer. While in case of anhydrous 2, Cu(tu)Cl rich in thiourea, between 180 and 240 °C, the main gaseous decomposition products are ammonia (NH), carbon disulfide (CS), and isothiocyanic acid (HNCS). At about 250 °C, gas-phase exothermic oxidation of CS and HNCS vapors occurs, resulting in a sudden release of sulfur dioxide (SO), carbonyl sulfide (COS), and hydrogen cyanide (HCN). Also a definite evolution of cyanamide (HNCN) is observed just above 250 °C. Between 350 and 500 °C, a more intense oxidation process of both organic condensed residues and copper(I) sulfides into copper(II)-oxo-sulfates appears, which is also indicated by intense evolution of CO, SO, and HNCN (and/or HNCO). Above 700 °C, the oxo-sulfates start to decompose resulting in repeated evolution of SO. All species identified by FTIR gas cell have been also confirmed by mass spectrometry. Evolution of HCl from Cu(tu)Cl ( 2) has been detected by either of the two EGA methods. [ABSTRACT FROM AUTHOR]

Abstract: A new and effective catalytic system using [N-benzyl DABCO]+[Cu4Cl5]− was developed for the palladium-free Sonogashira cross-coupling reactions of phenylacetylene with a variety of aryl halides. In this homogeneous catalytic system, 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane chloride, a quaternary ammonium salt containing a coordinating center, plays an important role and increases the efficiency of Cu(I) species during the reaction. A number of internal alkynes were produced in moderate to excellent yields, in short reaction times in DMF at 135°C. [Copyright &y& Elsevier]

Highlights: [•] The Cu2O films were fabricated under various oxidizing conditions by anodic oxidation. [•] The film quality was improved by decreasing the load current density. [•] The film quality means the crystal grain size, crystallinity and CuCl contamination. [•] The improvement of film quality was leading to more powerful Cu2O/Cu solar cells. [ABSTRACT FROM AUTHOR]

The ability of copper(I) chloride to catalyze the ring-opening isomerization of alkyl-, phenyl-, vinyl-, and cyclopropyl-substituted gem-chlorofluorocyclopropanes to chlorofluoroalkenes or chlorofluoroalkadienes was found. [ABSTRACT FROM AUTHOR]

Abstract: After the widespread ban of TBT, due to its severe impact on coastal biocoenoses, mainly related to its immunosuppressive effects on both invertebrates and vertebrates, alternative biocides such as Cu(I) salts and the triazine Irgarol 1051, the latter previously used in agriculture as a herbicide, have been massively introduced in combined formulations for antifouling paints against a wide spectrum of fouling organisms. Using short-term (60min) haemocyte cultures of the colonial ascidian Botryllus schlosseri exposed to various sublethal concentrations of copper(I) chloride (LC50 =281μM, i.e., 17.8mgCuL−1) and Irgarol 1051 (LC50 >500μM, i.e., >127mgL−1), we evaluated their immunotoxic effects through a series of cytochemical assays previously used for organotin compounds. Both compounds can induce dose-dependent immunosuppression, acting on different cellular targets and altering many activities of immunocytes but, unlike TBT, did not have significant effects on cell morphology. Generally, Cu(I) appeared to be more toxic than Irgarol 1051: it significantly (p <0.05) inhibited yeast phagocytosis at 0.1μM (∼10μgL−1), and affected calcium homeostasis and mitochondrial cytochrome-c oxidase activity at 0.01μM (∼1μgL−1). Both substances were able to change membrane permeability, induce apoptosis from concentrations of 0.1μM (∼10μgL−1) and 200μM (∼50mgL−1) for Cu(I) and Irgarol 1051, respectively, and alter the activity of hydrolases. Both Cu(I) and Irgarol 1051 inhibited the activity of phenoloxidase, but did not show any interactive effect when co-present in the exposure medium, suggesting different mechanisms of action. [Copyright &y& Elsevier]

Abstract: The copper-catalyzed radical cyclization (RC) of N-α-perchloroacyl cyclic ketene-N,X(X=O, NR, S)-acetals was studied. While the RC of N-acyl ketene-N,O-acetals was unsuccessful, the 5-endo cyclization of the other ketene acetals provided much better results, with the following order of cyclization efficiency: hexa-atomic cyclic ketene-N,NR-acetals

Direct transformation of five-membered zirconacycles to carbocyclic compounds is of great synthetic interest. The reaction of zirconacycles with electrophiles containing at least two reactive functional groups or an oxidant affords various carbocycles through cross coupling, addition, and/or oxidative coupling reactions. In this paper, we present our recent results on the zircona-cycle-mediated formation of carbocycles, including: (1) 1,1-cycloaddition of oxalyl dichloride with zirconacycles; (2) benzoquinone-promoted coupling of zirconacyclopentadienes in the presence of CuCl; (3) cycloaddition of zirconacyclopentadienes to quinones; (4) cycloaddition of zirconacyclopentadiene with 2-bromoacrylate, 2-bromoacrylaldehyde and 3-bromofuran-2,5-dione in the presence of CuCl; (5) one-pot coupling of two alkynes and an alkene to form cyclohexene derivatives via zirconacyclopentadienes; and (6) dianionic cycloaddition of decatetraenes with esters or acyl chlorides to form nine-membered carbocycles. [ABSTRACT FROM AUTHOR]

The carbon-carbon bond-forming radical reactions using indium(I) chloride and copper(I) chloride proceeded effectively through a single-electron transfer process in aqueous media. [ABSTRACT FROM AUTHOR]

Recyclable TEMPO-functionalized polyethylene glycol [PEG6000-(TEMPO)2] in combination with cuprous chloride were developed for biomimetic oxidation of a series of benzylic, allylic, heterocyclic alcohols, and 2-phenylethanol into the corresponding aldehydes or ketones in high selectivity and in moderate to high conversion in compressed CO2, which enhanced the catalytic activity as well as improved the selectivity. [ABSTRACT FROM AUTHOR]

The reaction of different aryl halides with aryl oxides catalyzed by CuCl in 1-butyl-3-methyl-imidazolium tetrafluoroborate [bmim][BF[sub4]] and 1-butyl-3-methyl-imidazolium hexafluorophosphate [bmim][PF[sub6]] ionic liquids to give diaryl ethers in 54-90% yields has been studied under mild reaction conditions. [ABSTRACT FROM AUTHOR]