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We present a series of borane‐tethered cyclic (alkyl)(amino)carbene (cAAC)‐copper complexes, including a borane‐capped Cu(I) hydride. This hydride is unusually hydridic and reacts rapidly with both CO2 and 2,6‐dimethylphenol at room temperature. Its reactivity is distinct from variants without a tethered borane, and the underlying principles governing the enhanced hydricity were evaluated experimentally and theoretically. These stoichiometric results were extended to catalytic CO2 hydrogenation, and the borane‐tethered (intramolecular) system exhibits ~3‐fold enhancement relative to an intermolecular system. [ABSTRACT FROM AUTHOR]

The ability to fabricate bimetallic clusters with atomic precision offers promising prospects for elucidating the correlations between their structures and properties. Nevertheless, achieving precise control at the atomic level in the production of clusters, including the quantity of dopant, characteristic of ligands, charge state of precursors, and structural transformation, have remained a challenge. Herein, we report the synthesis, purification, and characterization of a new bimetallic hydride cluster, [AuCu11(H){S2P(OiPr)2}6(C≡CPh)3] (AuCu11H). The hydride position in AuCu11H was determined using DFT calculations. AuCu11H comprises a ligand-stabilized defective fcc Au@Cu11 cuboctahedron. AuCu11H is metastable and undergoes a spontaneous transformation through ligand exchange into the isostructural [AuCu11(Cl){S2P(OiPr)2}6(C≡CPh)3] (AuCu11Cl) and into the complete cuboctahedral [AuCu12{S2P(OiPr)2}6(C≡CPh)4]+ (AuCu12) through an increase in nuclearity. These structural transformations were tracked by NMR and mass spectrometry. [ABSTRACT FROM AUTHOR]

Large-scale generation of high-purity hydrogen (H 2) from simple hydrolysis strategy is vital, but the traditional technologies remain problems of economy and efficiency. Herein, a new and low-cost technical route is highlighted to realize the litre-level and efficient production of high-purity H 2 from sodium hypophosphite (NaH 2 PO 2) hydrolysis at room temperature. The formation and stabilization of CuH species on the designed Cu–Cu 2 O/CuH catalyst plays a key role in stimulating a continuous reversible NaH 2 PO 2 hydrolysis cycle for H 2. Impressively, this new technology achieves the high generated rate of 3.3 L h−1•cm−2 for H 2 in alkaline media, which outperforms the other existing hydrolysis technologies. The proposed catalytic mechanism involves renewable CuH active species catalyzing the spontaneous reaction of NaH 2 PO 2 and H 2 O to form H 2 gas and phosphate. From the view of practical application, the developed coupling catalytic system also operates efficiently in deionized water, seawater and tap water solutions, shows unique interference immunity and high stability of convenient H 2 generation. A new strategy of H 2 production is developed by using Cu–Cu 2 O/CuH and NaH 2 PO 2 as synergistic catalytic system, which shows high generated rates and superior stability of high purity H 2 fuel at room temperature. The developed H 2 generation pathway has huge potential advantages over the traditional H 2 storage materials and water electrolysis. [Display omitted] • New and low-cost technical route of NaH 2 PO 2 hydrolysis for H 2 generation. • Litre-level and efficient production of high-purity H 2 (3.3 L•h-1•cm−2) at room temperature. • Renewable CuH active species catalyzing the NaH 2 PO 2 and H 2 O to H 2 gas and phosphate. • The developed technology shows high stability and applicability under different conditions. [ABSTRACT FROM AUTHOR]

Transition metal complexes, particularly copper hydrides, play an important role in various catalytic processes and molecular inorganic chemistry. This study employs synchrotron hard X‐ray spectroscopy to gain insights into the geometric and electronic properties of copper hydrides as potential catalysts for CO2 hydrogenation. The potential of high energy resolution X‐ray absorption near‐edge structure (HERFD‐XANES) and valence‐to‐core X‐ray emission (VtC‐XES) is demonstrated with measurement on Stryker's reagent (Cu6H6) and [Cu3(μ3‐H)(dpmppe)2](PF6)2 (Cu3H), alongside a non‐hydride copper compound ICu(dtbppOH) (Cuy−I). The XANES analysis reveals that coordination geometries strongly influence the spectra, providing only indirect details about hydride coordination. The VtC‐XES analysis exhibits a distinct signal around 8975 eV, offering a diagnostic tool to identify hydride ligands. Theoretical calculations support and extend these findings by comparing hydride‐containing complexes with their hydride‐free counterparts. [ABSTRACT FROM AUTHOR]

To realize economical and effective removal of hazardous 4-nitrophenol from the environment, we developed an easily recyclable ZnO nanowire array decorated with Cu nanoparticles. Its salix argyracea-shaped structure not only provides a platform to achieve stable and good dispersion of Cu nanoparticles, but also offers a great deal of catalytically active sites. The density functional theory calculations reveal that ZnO and Cu have a very beneficial synergistic effect on their catalytic capability. This synergy is ascribed to the electronic localization occurring at ZnO/Cu interface, which helps improve Cu nanoparticle's ability to adsorb electro-negatively 4-nitrophenolate ions and to capture hydrogen radicals, thereby accelerating the hydrogen transfer from metal hydride complex to 4-nitrophenol. Benefiting from these characteristics, it exhibits high efficiency and reusability towards the catalytic reduction of waste 4-nitrophenol to valuable 4-aminophenol with a rate constant of 43.02 × 10−3 s−1 and an average conversion of 96.5% in 90 s during 10 cycles. This activity is superior to that of most reported noble- or non-noble-metal powder, bulk, coating, and array catalysts, indicating its competitive advantages in cost and efficiency, as well as enticing application prospects. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) and transition metal complexes are two well-studied systems owing to their diverse applications and superior properties. Herein, GO/Fe3O4 nanostructure was prepared and used as a support for grafting Schiff base-Cu complex. This novel nanocatalyst was synthesized through modification of GO using Schiff base-Cu complex [GO/Fe3O4/Schiff base-Cu] being an eco-friendly, convenient and cost-effective procedure. The product was studied by various characterization techniques whose results revealed that the copper complex was grafted on the surface of the magnetic graphene oxide. The obtained nanocomposite shows chemical and thermal stabilities, as well as significant catalytic behavior. GO/Fe3O4/Schiff base-Cu nanocomposite was investigated as an efficient catalyst in the reduction of 4-nitrophenol and dyes, including methylene blue (MB) and Congo red (CR) with sodium borohydride in room temperature and aqueous solution by checking the reaction progress via visible–ultraviolent spectroscopy. Also, the catalytic activity of the novel nanocatalyst was evaluated in Knoevenagel condensation and Michael-type addition for the preparation of 2-amino 4H-chromene in ethanol/water green solvent at the temperature of 60 °C. The results showed that the synthesized nanocatalyst isolated magnetically can be reused for 4 times with no remarkable loss in the product yield. The synthesis method employed here demonstrated mainly the advantages of being ecofriendly and simple, excellent yields and high efficiency, usage of non-toxic solvent, as well as easiness of product isolation using ethanol. [ABSTRACT FROM AUTHOR]

Developing an efficient and long-lasting catalyst is of great importance for the reductive degradation of pollutants. Herein, we report a simple co-precipitation method to prepare copper-decorated iron oxide/activated carbon (AC) magnetic catalysts, in which copper-decorated iron oxide nanoparticles are uniformly distributed on coal-derived activated carbons (ACs). Both 4-nitrophenol and structurally complex dyes (Rhodamine B and Congo red) can be degraded by the copper-decorated iron oxide/AC nanocomposites in the presence of sodium borohydride. In particular, 4-nitrophenol can be reduced to 4-aminophenol within 6 minutes at room temperature, and the conversion efficiency remains above 96% after five cycles, while an external magnetic field easily recovers the catalyst during cycling. The excellent catalytic activity of copper-decorated iron oxide/AC can be attributed to the synergistic coupling between copper-decorated iron oxide nanoparticles and coal-based activated carbons, the high surface area of the AC and the small size of the copper-decorated iron oxide nanoparticles. The advantages of low cost, easy recovery, universal catalytic reduction, high activity, and durability make the proposed catalysts promising for a wide range of practical applications. [ABSTRACT FROM AUTHOR]

This study applies Density Functional Theory (DFT) to theoretically investigate the reaction mechanism of a copper complex catalyst facilitating the reaction between a terminal alkyne and α-bromo amide, enabling the formation of E-alkenes through C(sp2)–C(sp3) coupling. Initially, the study explores the reaction mechanism, identifying the predominant reaction pathway and the rate-determining step. Next, we discuss the addition reaction mode of copper hydride with terminal alkynes, determining the causes of regional and stereoselectivity. Subsequently, the reaction mechanism between the alkenyl copper intermediate and α-bromo amide is examined, including the discussion of alkyl fragment activation and introduction methods. Furthermore, the role of NHC ligands in catalyzing the single electron transfer process for C–Br bond activation is investigated. Finally, we analyze and discuss the reasons for the high energy barrier of the non-radical pathway. These investigations not only deepen our understanding of the reaction mechanisms of terminal alkynes and α-bromo amide catalyzed by copper but also provide valuable guidance for the future design of more efficient catalysts and reaction conditions. [ABSTRACT FROM AUTHOR]

Elucidating the structure–property relationships of ultra-small metal nanocluster with basic nuclear is of great significance for understanding the evolution mechanism in both the structures and properties of polynuclear metal nanoclusters. In this study, an ultra-small copper hydride (CuH for short) nanocluster was simply synthesized with high yield, and the large-scale preparation was also achieved. Single crystal X-ray diffractometer (SC-XRD) analysis shows that this copper NC contains a tetrahedral Cu4 core co-capped by four PPh2Py ligands and two Cl in which the existence of the central H atom in tetrahedron was further identified experimentally and theoretically. This CuH nanocluster exhibits bright yellow emission, which is proved to be the mixture of phosphorescence and fluorescence by the sensitivity of both emission intensity and lifetime to O2. Furthermore, the temperature-dependent emission spectra and density functional theory (DFT) calculations suggest that the luminescence of CuH mainly originates from the metal-to-ligand charge transfer and cluster-centered triplet excited states. This work offers new insights into understanding the structure–property relationship of basic nuclear CuH nanocluster. [ABSTRACT FROM AUTHOR]

Catalytic asymmetric hydroboration of fluoroalkyl‐substituted alkenes is a straightforward approach to access chiral small molecules possessing both fluorine and boron atoms. However, enantioselective hydroboration of fluoroalkyl‐substituted alkenes without fluorine elimination has been a long‐standing challenge in this field. Herein, a copper‐catalyzed hydroboration of difluoroalkyl‐substituted internal alkenes with high levels of regio‐ and enantioselectivities is reported. The native carbonyl directing group, copper hydride system, and bisphosphine ligand play crucial roles in suppressing the undesired fluoride elimination. This atom‐economic protocol provides a practical synthetic platform to obtain a wide scope of enantioenriched secondary boronates bearing the difluoromethylene moieties under mild conditions. Synthetic applications including functionalization of biorelevant molecules, versatile functional group interconversions, and preparation of difluoroalkylated Terfenadine derivative are also demonstrated. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Despite the paramount applications of organofluorine compounds in life and materials sciences, efficient strategies for stereoselectively constructing the C(sp3)‐CF2R bond at the stereogenic center remain limited. Here, we report a copper‐catalyzed hydrodifluoroallylation of cyclopropenes and alkenyl boronates with 3,3‐difluoroallyl sulfonium salts (DFASs). The use of DFASs overcomes the previous challenge of suppressing the reduction of fluoroalkylating reagents with M‐H species. The reaction provides an array of gem‐difluoroallyl cyclopropanes and borylalkanes with high efficiency and stereoselectivity under mild reaction conditions. Using chiral phosphine ligand could provide gem‐difluoroallyl borylalkanes with high enantioselectivities, paving a new way for the catalytic asymmetric fluoroalkylation with ubiquitous alkenes. The advantages of this protocol are synthetic convenience, high functional group tolerance, and the synthetic versatility of the resulting gem‐difluoroallyl cyclopropanes and borylalkanes. The synthetic utility of this approach has also been demonstrated by the diversified transformations of the gem‐difluoroallylated products and the rapid synthesis of bioactive molecule analogs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Despite the paramount applications of organofluorine compounds in life and materials sciences, efficient strategies for stereoselectively constructing the C(sp3)‐CF2R bond at the stereogenic center remain limited. Here, we report a copper‐catalyzed hydrodifluoroallylation of cyclopropenes and alkenyl boronates with 3,3‐difluoroallyl sulfonium salts (DFASs). The use of DFASs overcomes the previous challenge of suppressing the reduction of fluoroalkylating reagents with M‐H species. The reaction provides an array of gem‐difluoroallyl cyclopropanes and borylalkanes with high efficiency and stereoselectivity under mild reaction conditions. Using chiral phosphine ligand could provide gem‐difluoroallyl borylalkanes with high enantioselectivities, paving a new way for the catalytic asymmetric fluoroalkylation with ubiquitous alkenes. The advantages of this protocol are synthetic convenience, high functional group tolerance, and the synthetic versatility of the resulting gem‐difluoroallyl cyclopropanes and borylalkanes. The synthetic utility of this approach has also been demonstrated by the diversified transformations of the gem‐difluoroallylated products and the rapid synthesis of bioactive molecule analogs. [ABSTRACT FROM AUTHOR]

This document is the contents list for an issue of the journal Chemical Communications, published by the Royal Society of Chemistry. It provides a summary of calixarene-based fluorescent sensors developed in the past five years, as well as feature articles on precision nanoengineering for functional self-assemblies across length scales. The document also includes information for authors who wish to submit material for publication, guidelines for reproducing published contributions, and a list of featured articles and communications that have been published in the journal. It covers a range of topics in chemistry, including the synthesis of complex oxide thin films, self-assembled perovskite quantum dots, and regioselective synthesis of indazolo[2,3-a]-quinazolines. The document concludes with information about copyright and the use of the journal's content. [Extracted from the article]

Eight new copper(I) triphenylphosphine complexes of bulky 5‐substituted‐2‐iminopyrrolyl ligands [Cu{κ2N,N′‐5‐R‐NC4H2–2‐C(H) = N(2,6‐iPr2C6H3)}(PPh3)n] (for n = 2: R = 2,6‐Me2C6H3 (1), 3,5‐(CF3)2C6H3 (2); for n = 1: R = 2,4,6‐iPr3C6H2 (3), CPh3 (4), 2,6‐(OMe)2C6H3 (5), 2,4,6‐Ph3C6H2 (6), 2,6‐Me2C6H3 (7), 3,5‐(CF3)2C6H3 (8)) are presently reported. The complexes were prepared in good yields by: (1) the reaction of the previously reported binuclear complexes [Cu{κN,κN'‐5‐R‐NC4H2‐2‐C(H) = N(2,6‐iPr2C6H3)}]2 (D1–D6) with triphenylphosphine (PPh3); (2) the reaction of the respective 5‐R‐2‐iminopyrrolyl potassium salts (KL1–KL3 and KL5) and [Cu(NCMe)2(PPh3)2]BF4; or (3) the abstraction of one PPh3 ligand present in complexes 1 and 2 with one equivalent of tris(pentafluorophenyl)borane (only for complexes 7 and 8, respectively). All complexes were characterized by NMR spectroscopy, elemental analysis and, in selected cases, by single crystal X‐ray diffraction. The single crystal X‐ray diffraction structures of 1, 3, and 5–7 displayed tetrahedral (for 1) and trigonal planar (for 3 and 5–7) coordination geometries. All complexes catalyzed the 1,4‐hydroboration of some α,β‐unsaturated (E)‐2‐enals with pinacolborane (HBPin), with 1,4:1,2‐addition selectivities as high as 29:1, the maximum turnover frequencies being equal to 9.9 min−1, and the 1,4‐hydroboration selectivity being favored by increasing steric protection of the 5‐substituted‐2‐iminopyrrolyl scaffold. Additionally, these complexes also catalyzed the hydroboration of an array of other aldehydes, reaching TOFs as high as 9.9 min−1. A combination of control experiments suggests that the catalyst system operates via a non‐classical copper‐hydride outer sphere route. [ABSTRACT FROM AUTHOR]

The synergistic effects of metal complex nanoparticles in remediation of environment had opened a versatile field of research as providing differential attractive forces for a given pollutant on their surfaces. Herein, trimetallic nanoparticles of silver, copper and cobalt (Ag–Cu–Co TNPs) were prepared via chemical reduction method using sodium borohydride as reductant which were then characterized through SEM, EDX, XRD and FT-IR analytical techniques. As model dye, acid blue 7 was adsorbed on the surface of fabricated particles utilizing batch adsorption approach. The adsorption conditions like temperature, adsorbent dosage, pH, and contact time were optimized to get maximum adsorption of the selected dye which were; 333 K, 0.01 g, pH 6 and 30 min respectively. The adsorption data were analyzed using kinetic and isotherm models, with the linear pseudo 2nd order kinetics and Langmuir models being the most suitable. The maximum adsorption capacity at 333 K was found to be 74.07 mg/g. Thermodynamic variables such as entropy (ΔS°), enthalpy (ΔH°), and Gibbs free energy (ΔG°) changes were calculated to understand the adsorption feasibilities. Results indicated that the adsorption process was endothermic (ΔH° = 6.867 KJ mol−1) and spontaneous ΔG° (J mol−1) −219.2, −702.9 and −1086.6 at 293 K, 313 K and 333 K respectively. The entropy change (ΔS° = 24.185 J mol−1 K−1) suggested an increased disorder at the solid–solution interface during adsorption. [ABSTRACT FROM AUTHOR]

Catalytic chemo‐, regio‐ and enantioselective construction of allyl‐Cu complexes generated from a Cu−H addition to trans‐1,3‐dienes followed by in situ addition to anhydrides to construct homoallylic alcohols is presented. This method is distinguished by a characteristic pathway to generate enantiomerically enriched allyl‐Cu species, which react with a wide range of anhydrides in high chemo‐, regio‐ and stereoselectivity. Functionalization of homoallylic alcohol products provides useful building blocks which are otherwise difficult to obtain. [ABSTRACT FROM AUTHOR]

Herein, we report a comprehensive computational study to understand the stereoinduction of (R)-SEGPHOS chiral diphosphine ligand in copper(I) hydride (CuH)-catalyzed enantioselective incorporation of CO2 with styrene. Mechanistic studies disclose that the stereoselectivity of the final reductive hydroxymethylation product is collectively controlled by the steps of 1,2-hydrocupration of styrene and CO2 insertion into the Cu–C bond. The multimodal stereochemical analyses, including the topographic steric mapping of the chiral (R)-SEGPHOS-ligated CuH catalyst, distortion/interaction, and intermolecular non-covalent interaction analysis on the 1,2-hydrocupration transition states, consistently point to the steric shielding from the P-substituents of the (R)-SEGPHOS ligand to the substrate as the origin of π-facial selectivity in the 1,2-hydrocupration step. Both (R)-SEGPHOS ligands bearing the P-DMTB and P-phenyl substituents can provide sufficient steric repulsion for shielding the re-face approach of the substrate to the Cu–H bond, and thus the (S)-alkylcopper(I) intermediates could be yielded with high enantioselectivity. By contrast, the stereoselectivity of CO2 insertion into (S)-alkylcopper(I) intermediate is primarily determined by the ligand-CO2 dispersion stabilizing interaction. Relative to the (R)-SEGPHOS ligand with the P-phenyl substituents, the substantially enhanced dispersion stabilizing interactions from the P-DMTB substituents of (R)-SEGPHOS ligand to CO2 could help raise the favorability of the inner-sphere CO2 insertion into the Cu–C bond, and thus allow the construction of C–CO2 bond with outstanding stereoselectivity. [ABSTRACT FROM AUTHOR]

Point defects in nanoparticles have long been hypothesized to play an important role in governing the particle's electronic structure and physicochemical properties. However, single point defects in material systems usually exist with other heterogeneities, obscuring the chemical role of the effects. Herein, we report the synthesis of novel atomically precise, copper hydride nanoclusters (NCs), [Cu28H10(C7H7S)18(TPP)3] (Cu28; TPP: triphenylphosphine; C7H7S: o‐thiocresol) with a defined defect in the gram scale via a one‐pot reduction method. The Cu28 acts as a highly selective catalyst for C−C cross‐couplings. The work highlights the potential of defective NCs as model systems for investigating individual defects, correlating defects with physiochemical properties, and rationally designing new nanoparticle catalysts. [ABSTRACT FROM AUTHOR]

Metal nanomaterials, such as silver and copper, are often incorporated into commercial textiles to take advantage of their Antibacterial and antiviral properties. The goal of this study was to identify the most parsimonious method for the synthesis of silver, copper, or silver/copper bimetallic treated textiles. To accomplish this eight different methods were employed to synthesize silver, copper, and silver/copper functionalized cotton batting textiles. Using silver and copper nitrate as precursors, different reagents were used to initiate/catalyze the deposition of metal, including: (1) no additive, (2) sodium bicarbonate, (3) green tea, (4) sodium hydroxide, (5) ammonia, (6, 7) sodium hydroxide/ammonia at a 1:2 and 1:4 ratio, and (8) sodium borohydride. The use of sodium bicarbonate as a reagent to reduce silver onto cotton has not been used previously in literature and was compared to established methods. All synthesis methods were performed at 80 °C for one hour following textile addition to the solutions. The products were characterized by x-ray fluorescence (XRF) analysis for quantitative determination of the metal content and x-ray absorption near edge structure (XANES) analysis for silver and copper speciation on the textile. Scanning electron microscopy (SEM) with energy dispersive x-ray (EDX) and size distribution inductively coupled plasma mass spectrometry (ICP-MS) were used to further characterize the products of the sodium bicarbonate, sodium hydroxide, and sodium borohydride synthesis methods following ashing of the textile. For the silver treatment methods (1 mM Ag +), sodium bicarbonate and sodium hydroxide resulted in the highest amounts of silver on the textile (8900 mg Ag/kg textile and 7600 mg Ag/kg textile) and for copper treatment (1 mM Cu +) the sodium hydroxide and sodium hydroxide/ammonium hydroxide resulted in the highest amounts of copper on the textile (3800 mg Ag/kg textile and 2500 mg Ag/kg textile). Formation of copper oxide was dependent on the pH of the solution, with 4 mM ammonia and other high pH solutions resulting in majority of the copper on the textile existing as copper oxide, with smaller amounts of ionic-bound copper. The identified parsimonious methods will lend themselves to the efficient manufacturing of antibacterial and antiviral textiles, or the development of multifunctionalized smart textiles. [ABSTRACT FROM AUTHOR]

A neutral polyhydrido copper cluster, [Cu27H15{S2CNnBu2}12] (abbreviated as [Cu27H15]), was prepared by the reaction of dithiocarbamates (dtc), Cu(I) salts and NaBH4. The isolated cluster provides insights into core engineering, demonstrating its novel ability to reversibly add or remove one copper atom from the cluster core. Single-crystal X-ray analysis reveals that the new core–shell structure exhibits a Cu24 rhombicuboctahedral outer cage and an inner Cu3 triangular kernel. The two core–shell clusters, [Cu27H15{S2CNnBu2}12] and previously published [Cu28H15(S2CNnBu2)12]+ (abbreviated as [Cu28H15]+), are only differentiated by one copper atom in their inner core. Importantly, we demonstrate core engineering with the controllable reversible transition between an irregular Cu4 tetrahedron and a Cu3 triangle, whilst maintaining their outer Cu24 shell intact. The 15 hydride atoms in [Cu27H15], coordinated in three different modes, are co-incident with the hydride positions in [Cu28H15]+. The degradation of [Cu27H15] in solution or the addition of one eq. of Cu(I) ions leads to the conversion of [Cu27H15] into [Cu28H15]+, while the reverse transformation can be achieved by the addition of either formic acid or a reducing agent to [Cu28H15]+. A dicationic species was observed in the ESI mass spectrum, and the composition is formulated as [Cu56H30(S2CNnBu2)24]2+, a dimer of [Cu27H15(S2CNnBu2)12 + Cu+]22+. The dimeric species was further explored by DFT calculations, suggesting that the lowest energy structure consists of a [Cu28H15]+ and a [Cu27H15] cluster connected through one Cu+ atom bridge. As a result, [Cu27H15] is considered an intermediate species in the formation of the more stable [Cu28H15]+ nanoball. [ABSTRACT FROM AUTHOR]

A near thermal two-step catalytic cycle for the selective release of hydrogen from formic acid by mononuclear cuprate anions was revealed using multistage mass spectrometry experiments, deuterium labelling and DFT calculations. In gas-phase ion-molecule reactions, mononuclear copper hydride anions [(L)Cu(H)]− (where L = H−, O2CH−, BH4− and CN−) were found to react with formic acid (HCO2H) to yield [(L)Cu(O2CH)]− and H2. The copper formate anions [(L)Cu(O2CH)]− can decarboxylate via collision-induced dissociation (CID) to reform the copper hydride [(L)Cu(H)]−, thereby closing the two-step catalytic cycle. Analogous labelling experiments with d1-formic acid (DCO2H) reveal that the decarboxylation process also occurs spontaneously. A kinetic study was carried out to provide further insights into the species involved in this reaction. Energetics from density functional theory (DFT) calculations show that the key decarboxylation step can occur without CID, thus in support of experimental observations. [ABSTRACT FROM AUTHOR]

α‐Stereogenic allyl metalloids are versatile synthetic intermediates which can undergo various stereocontrolled transformations. Most existing methods to prepare α‐stereogenic allyl metalloids involve multi‐step sequences that curtail the number of compatible substrates and are limited to the synthesis of boronates. Here, we report a general method for the enantioselective preparation of α‐stereogenic allyl metalloids utilizing dual CuH‐ and Pd‐catalysis. This approach leverages a stereoretentive Cu‐to‐Pd transmetalation of an in situ generated alkyl copper species to allow access to enantioenriched allyl silanes, germanes, and boronate esters with broad functional group compatibility. [ABSTRACT FROM AUTHOR]

The electronic absorption spectra of CuH and AgH molecules are calculated using the analytical expression for the spectral density related to the thermal dipole time correlation function. In addition, the vibronic transition probabilities between the initial and final states are determined by calculating the transition dipole moments and the Franck-Condon factors using the LEVEL program. The spectroscopic constants recently obtained from MRCI + SOC calculations are used to calculate the absorption spectral line shapes of CuH and AgH molecules and plotted in the time and frequency domains for the vibronic transitions from the ground state Ω = 0+(I) to the excited states Ω = 0+(II), 0+(III), 1(I), 1(II), 1(III), and 1(IV) for CuH and to the excited states Ω = 0+(II), 0+(III), 0+(IV), 1(II), 1(III), 1(IV), 1(V), and 1(VI) for AgH. [ABSTRACT FROM AUTHOR]

• Flake ZnO was prepared by seed-assisted hydrothermal method. • ZnO was modified by copper doping and oxygen vacancy synergistically. • The antibacterial performance of Cu-ZnO-R has been significantly improved. In this study, copper-doped zinc oxide nanocomposites were prepared, and the oxygen vacancy was regulated by sodium borohydride. The structure of the materials was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscope (TEM), Inductively coupled plasma mass spectrometry (ICP-MS) and Electron paramagnetic resonance (EPR). The photocatalytic efficiency of the 5 % Cu-doped ZnO sample (denoted as Cu-ZnO-R) was evaluated by testing its ability to kill gram-negative Escherichia coli and gram-positive Staphylococcus aureus. The results showed that 5 % Cu-ZnO-R could completely kill the target bacteria with a concentration of 2 × 107 CFU/mL within 20 min under light. EPR indicates that ·OH and ·O 2 − are the primary active oxygen components in photocatalytic reaction system. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of copper nanoparticles (NP) at mild conditions using dual biopolymer, chitosan-alginate, modified magnetic nanoparticles as a protecting/stabilizing agent and sodium borohydride as a reducing agent. The obtained nanocomposite (Fe3O4/Chitosan-Alginate/Cu NPs) were physico-chemically assessed over FT-IR, FE-SEM, EDX, elemental mapping, ICP-OES, TEM, VSM, and XRD studies. The as-synthesized Fe3O4/Chitosan-Alginate/Cu NPs were explored as an efficient heterogeneous nanocatalyst in the aryl and heteroaryl C–N cross-coupling reactions with considerably high yields under mild conditions. The catalyst was isolated and reused for nine times with reproducible catalytic activity. [ABSTRACT FROM AUTHOR]

The asymmetric hydroaminocarbonylation of olefins represents a straightforward approach for the synthesis of enantioenriched amides, but is hampered by the necessity to employ CO gas, often at elevated pressures. We herein describe, as an alternative, an enantioselective hydrocarbamoylation of alkenes leveraging dual copper hydride and palladium catalysis to enable the use of readily available carbamoyl chlorides as a practical carbamoylating reagent. The protocol is applicable to various types of olefins, including alkenyl arenes, terminal alkenes, and 1,1‐disubstituted alkenes. Substrates containing a diverse range of functional groups as well as heterocyclic substructures undergo functionalization to provide α‐ and β‐chiral amides in good yields and with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

We present a series of borane-tethered cyclic (alkyl)(amino)carbene (cAAC)-copper complexes, including a borane-capped Cu(I) hydride. This hydride is unusually hydridic and reacts rapidly with both CO 2 and 2,6-dimethylphenol at room temperature. Its reactivity is distinct from variants without a tethered borane, and the underlying principles governing the enhanced hydricity were evaluated experimentally and theoretically. These stoichiometric results were extended to catalytic CO 2 hydrogenation, and the borane-tethered (intramolecular) system exhibits ~3-fold enhancement relative to an intermolecular system., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Low‐nuclearity copper hydrides are rare and few well‐defined dicopper hydrides have been reported. Herein, we describe the first example of a structurally characterized anionic dicopper hydride complex. This complex does not display typical reactivity associated with low‐nuclearity copper hydrides, such as alcoholysis or insertion reactions. Instead, its stoichiometric and catalytic reactivity is akin to that of copper hydride clusters. The distinct reactivity is ascribed to the robust dinuclear core that is bound tightly within the dinucleating ligand scaffold. [ABSTRACT FROM AUTHOR]

The magnetic nanoparticles of Fe3O4 were synthesized through a solid-state reaction of hydrated iron (III) chloride, hydrated iron (II) chloride and NaOH, and then purified by calcination at high temperature. In order to protect ferrite nanoparticles from oxidation and agglomeration, and to manufacture a novel catalytic system of anchored copper on the magnetic substrate, the Fe3O4 was core-shelled by adding tetraethyl orthosilicate. Next, the prepared Fe3O4@SiO2 was supported by phosphomolybdic acid (PMA) as the second layer of nanocomposite at 80 °C in 30 h. Eventually, the new nanocomposite of Fe3O4@SiO2-PMA-Cu was successfully synthesized by adding copper (II) chloride solution and solid potassium borohydride. The structure of magnetic nanocatalyst was acknowledged through different techniques such as EDS, VSM, XRD, TEM, FT-IR, XPS, TGA, BET and FESEM. The synthesis of β-thiolo/benzyl-1,2,3-triazoles from various thiiranes, terminal alkynes and sodium azide was catalyzed by Fe3O4@SiO2-PMA-Cu nanocomposite in aqueous medium. In order to obtain the optimum condition, the effects of reaction time, temperature, catalyst amount and solvent were gauged. The recycled catalyst was used for several consecutive runs without any loss of activity. [ABSTRACT FROM AUTHOR]

The Cover Feature creatively represents our research on copper hydrides, illustrating a helicopter with a synchrotron as rotor blades landing on a CuH platform. The helicopter symbolizes the precision and advanced technology of synchrotron hard X‐ray spectroscopy used in our study. The CuH platform, which is simultaneously a magnifying glass, highlights the focus on copper hydride complexes. More information can be found in the Research Article by M. Bauer and co‐workers (DOI: 10.1002/chem.202400357)...By Lorena Fritsch; Pia Rehsies; Wael Barakat; Deven P. Estes and Matthias BauerReported by Author; Author; Author; Author; Author [Extracted from the article]

Modification of μ 4 -H trigonal pyramidal (tp) geometry in PtH 2 Cu 14 -dtp into μ 5 -H trigonal bipyramidal (tbp) in PtH 2 Cu 14 -dtc can be achieved through the replacement of supporting dithiophosphate (dtp) with dithiocarbamate (dtc) ligands. [Display omitted] An atomically precise heteroleptic Pt-doped Cu-rich hydride nanocluster [PtH 2 @Cu 14 (dtc) 6 (C 2 Ph) 6 ] (PtH 2 Cu 14 -dtc) has been successfully synthesized. This was achieved by introducing a discrete Pt(II) precursor to the copper hydride nanocluster [Cu 28 H 15 (dtc) 12 ](PF 6) in the presence of terminal alkynes. The structure of PtH 2 Cu 14 determined by X-ray diffraction reveals a bicapped icosahedral copper(I) cage encapsulating a linear platinum dihydride [PtH 2 ]2- unit. The interstitial hydrides are arranged in a trigonal bipyramidal (tbp) geometry with a five-coordinated hydride as confirmed by 2H NMR and ESI-MS measurements. [ABSTRACT FROM AUTHOR]

Copper hydrides are important hydrogenation catalysts, but their poor stability hinders the practical applications. Ligand engineering is an effective strategy to tackle this issue. An amidinate ligand, N,N′-Di(5-trifluoromethyl-2-pyridyl)formamidinate (Tf-dpf) with four N-donors has been applied as a protecting agent in the synthesis of stable copper hydride clusters: Cu11H3(Tf-dpf)6(OAc)2 (Cu11) with three interfacial μ5-H and [Cu12H3(Tf-dpf)6(OAc)2]·OAc (Cu12) with three interstitial μ6-H. A solvent-triggered reversible interconversion between Cu11 and Cu12 has been observed thanks to the flexibility of Tf-dpf. Cu11 shows high activity in the reduction of 4-nitrophenol to 4-aminophenol, while Cu12 displays very low activity. Deuteration experiments prove that the type of hydride is the key in dictating the catalytic activity, for the interfacial μ5-H species in Cu11 are involved in the catalytic cycle whereas the interstitial μ6-H species in Cu12 are not. This work highlights the role of hydrides with regard to catalytic hydrogenation activity. Copper hydrides have been studied for their exciting structural chemistry and applications in hydrogenation catalysis. Here, the authors uncover the role of the amidinate ligand in yielding two closely related copper hydride clusters with quite different catalytic hydrogenation activity. [ABSTRACT FROM AUTHOR]

The tremendous success of stereogenic carbon compounds has never ceased to inspire researchers to explore the potentials of stereogenic silicon compounds. Intermolecular C–H silylation thus represents the most versatile and straightforward strategy to construct C–Si bonds, however, its enantioselective variant has been scarcely reported to date. Herein we report a protocol that allows for the enantioselective intermolecular C–H bond silylation, leading to the construction of a wide array of acyclic stereogenic Si–H compounds under simple and mild reaction conditions. Key to the success is (1) a substrate design that prevents the self-reaction of prochiral silane and (2) the employment of a more reactive rhodium hydride ([Rh]-H) catalyst as opposed to the commonly used rhodium chloride ([Rh]-Cl) catalyst. This work unveils opportunities in converting simple arenes into value-added stereogenic silicon compounds. Construction of chiral organosilicon compounds could have implications in photophysical, biological, and chemical fields, as silicon is isoelectronic with carbon, and can mimic carbon atoms while providing slightly different properties. Here the authors present an intermolecular, enantioselective C–H silylation of heterocycles via rhodium catalysis. [ABSTRACT FROM AUTHOR]

CuH and CuBpin are versatile catalysts and intermediates in organic chemistry. However, studies that involve both CuH and CuBpin in the same reaction is still rarely reported due to their high reactivity. Now, a study on CuH‐ and CuBpin‐catalyzed borylative methylation of alkyl iodides with CO as the C1 source is reported. Various one carbon prolongated alkyl boranes (RCH2Bpin and RCH(Bpin)2) were produced in moderate to good yields from the corresponding alkyl iodides (RI). In this cooperative system, CuH reacts with alkyl iodide faster than CuBpin. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to improve the performance of sodium borohydride in reducing indigo at room temperature, the divalent copper ion complex was combined with electrochemical technology for the reduction of indigo by sodium borohydride. Design/methodology/approach: According to the K/S value of the dyed cloth sample, find a more suitable ligand for the copper ion in the catholyte. Response surface analysis tests were performed to evaluate the effects of sodium borohydride concentration, sodium hydroxide concentration and copper sulfate pentahydrate concentration on the reduction potential of the dye solution and the K/S value of the dyed fabric samples. Findings: Sodium gluconate was found to be a more suitable ligand for copper ions in catholyte. The effects of NaOH concentration as well as the interaction of NaBH4 and NaOH on the reduction potential of the catholyte and the K/S value of the dyed fabric samples were extremely significant. The optimal concentrations of NaBH4, NaOH and CuSO4•5H2O were 0.5, 2.5 and 0.65 g/L. In the case of the optimized condition, the absolute value of the reduction potential was 968, and the K/S value was 11.92, which is comparable with that of the conventional reduction process with sodium dithionite. Originality/value: The divalent copper ion complex combined with electrochemical technology was applied in the process of reducing indigo with NaBH4 at room temperature. [ABSTRACT FROM AUTHOR]

Copper hydrides are very useful in hydrogenation reactions. We report a stable Stryker-type copper hydride reagent protected by hemilabile phosphines: [Cu8H6(dppy)6](OTf)2 (Cu8-H, dppy = diphenylphosphino-2-pyridine). The metal core of this cluster has a bicapped octahedral configuration, and the copper-bound hydrides each triply bridges over a triangular face of the octahedron. This cluster is attractive due to its facile preparation and excellent stability under ambient conditions. The comparable activity and selectivity both in the stoichiometric and catalytic reactions make Cu8-H a promising alternative to Stryker's reagent. [ABSTRACT FROM AUTHOR]

Reactions of [(NHC)CuH] 2 dimers (NHC = IPr*, 6Dipp) with PhN=NPh, N 3 Ad, pyrazine, and N 2 O produced the corresponding monomeric, two-coordinate diphenyl hydrazido, triazenido, pyrazin-1(2H)-yl, and hydroxide Cu(I) complexes. [Display omitted] • Stoichiometric reactions of [(NHC)CuH] 2 (NHC = IPr*, 6Dipp) with unsaturated nitrogen-based substrates of PhN = NPh, N 3 Ad, pyrazine, and N 2 O at mild conditions. • Spectroscopic and structural chacterizations of stable two-coordinate Cu(I) complexes containing triazenido, diphenyl hydrazido, pyrazinyl, and hydroxide ligands. • The isolation of low-coordinate triazenido and hydrazido species highlight the unique stability of linear (NHC)Cu(I) complexes. The stoichiometric and catalytic reactions of Cu-H dimers supported by N -heterocyclic carbenes (NHCs) have mainly focused on the insertions of aldehydes, ketones, CO 2 , and unsaturated hydrocarbons. In this report, we investigated the stoichiometric reactions of dimeric [(NHC)CuH] 2 (NHC = IPr*, 6Dipp) with unsaturated nitrogen-based substrates of PhN=NPh, N 3 Ad, pyrazine, and N 2 O. The spectroscopic and structural chacterizations of the resulting monomeric, two-coordinate Cu(I) complexes containing diphenyl hydrazido, triazenido, pyrazinyl, and hydroxide ligands are discussed. The hydrazido complex of (IPr*)Cu(NPh-NHPh) and triazenido complex of (IPr*)Cu(HNNNAd) are resistant to N N bond cleavage and loss of N 2 , respectively, to form the corresponding amido complexes even when heated at 80 °C over several hours. [ABSTRACT FROM AUTHOR]

Three series of copper hydride clusters [Cu8H6L6]2+ (1), [Cu4HX2L4]+ where X− = Cl− (2a), Br− (2b), I− (2c), N3− (2d) and SCN− (2e), and [Cu4HX3L3] where X− = Br− (3b) and I− (3c) (L = 2-(diphenylphosphino)pyridine, dppy) were synthesized and characterized by single-crystal X-Ray crystallography and standard spectroscopic techniques. The metal core of 1, Cu8, can be described as a bicapped octahedron, while those of 2 and 3 series adopt tetrahedral structures. The hydride positions were deduced from difference electron density maps and corroborated by NMR and DFT calculations. For 1, there are two μ4-H−, one each in the two tetrahedral cavities of the two capping atoms and four μ3-H− on the six triangular faces around the waist of the octahedron. For [Cu4HX2L4]+ and [Cu4HX3L3] series, the single μ4-H− resides in the center of the Cu4 tetrahedron. It was found that these three series of copper clusters are intimately connected and can convert from one to another under specific reaction conditions. Their transformation pathways were investigated in detail. Spontaneous resolution to form optically pure enantiomeric single crystals was observed for [Cu4H(SCN)2L4]+ (2e) and [Cu4HBr3L3] (3b). Photoluminescence was observed for [Cu4HX2L4]+, as well as [Cu4HX3L3] with strong emissions from green to yellow regions. [ABSTRACT FROM AUTHOR]

C–Si bonds were constructed by utilizing copper hydride-catalyzed asymmetric hydrosilylation of 1,2-dihydroquinolines, affording various chiral 4-silyl-1,2,3,4-tetrahydroquinolines in good yields and enantioselectivity. In addition, the C–Si bonds were transformed into C–O bonds with retention of stereochemistry through the Tamao oxidation, giving a series of useful 4-hydroxy-1,2,3,4-tetrahydroquinolines. This method with the enantioselective introduction of silyl groups provides an option to adjust bioactive properties of tetrahydroquinolines. [ABSTRACT FROM AUTHOR]

The reaction of ToMTl (ToM=tris(4,4‐dimethyl‐2‐oxazolinyl)phenylborate) and CuBr2 in benzene at 60 °C provides ToMCuBr (1) as an entry‐point into tris(oxazolinyl)phenylborato copper chemistry. ToMCuOtBu (2) and ToMCuOAc (3) are prepared by the reactions of ToMCuBr with KOtBu and NaOAc, respectively. ToMCuOtBu is transformed into (ToMCuOH)2 (4) through hydrolysis. NMR, FT‐IR, and EPR spectroscopies are used to determine the electronic and structural properties of these copper(II) compounds, and the solid‐state structures were characterized by X‐ray crystallography. Reduction of copper is observed upon treatment of ToMCuOtBu with phenylsilane in an attempt to synthesize monomeric copper(II) hydride. ToMCu (5) and ToM2Cu (6) were independently synthesized and characterized for comparison. [ABSTRACT FROM AUTHOR]

Cuproptosis has drawn enormous attention in antitumor material fields; however, the responsive activation of cuproptosis against tumors using nanomaterials with high atom utilization is still challenging. Herein, a copper-based nanoplatform consisting of acid-degradable copper hydride (CuH) nanoparticles was developed via a microfluidic synthesis. After coating with tumor-targeting hyaluronic acid (HA), the nanoplatform denoted as HA-CuH-PVP (HCP) shows conspicuous damage toward tumor cells by generating Cu + and hydrogen (H 2 ) simultaneously. Cu + can induce apoptosis by relying on Fenton-like reactions and lead to cuproptosis by causing mitochondrial protein aggregation. Besides, the existence of H 2 can enhance both cell death types by causing mitochondrial dysfunction and intracellular redox homeostatic disorders. In vivo experimental results further exhibit the desirable potential of HCP for killing tumor cells and inhibiting lung metastases, which will broaden the horizons of designing copper-based materials triggering apoptosis and cuproptosis for better antitumor efficacy.

Arenes with β‐stereogenic centers are important substructures in pharmaceuticals and natural products. We have developed an asymmetric anti‐Markovnikov hydroarylation of 1,1‐disubstituted olefins by dual palladium and copper hydride catalysis as a convenient and general approach to access these substructures. This efficient one‐step process addresses several limitations of the traditional stepwise approaches. The use of cesium benzoate as a base and a common phosphine ligand for both the Cu‐ and Pd‐catalyzed processes were important discoveries that allow these challenging olefin substrates to be efficiently transformed. A variety of aryl bromide coupling partners, including numerous heterocycles, were coupled with 1,1‐disubstituted alkenes to generate arenes with β‐stereogenic centers. [ABSTRACT FROM AUTHOR]

We numerically investigate the impact of Coulomb collisions on the ion dynamics in high-Z, solid density caesium hydride and copper targets, irradiated by high-intensity (), ultrashort (∼10 fs), circularly polarized laser pulses, using particle-in-cell simulations. Collisions significantly enhance electron heating, thereby strongly increasing the speed of a shock wave launched in the laser-plasma interaction. In the caesium hydride target, collisions between the two ion species heat the protons to ∼100−1000 eV temperatures. However, in contrast to previous work (A E Turrell et al 2015 Nat. Commun. 6 8905), this process happens in the upstream only, due to nearly total proton reflection. This difference is ascribed to distinct models used to treat collisions in dense/cold plasmas. In the case of a copper target, ion reflection can start as a self-amplifying process, bootstrapping itself. Afterwards, collisions between the reflected and upstream ions heat these two populations significantly. When increasing the pulse duration to 60 fs, the shock front more clearly decouples from the laser piston, and so can be studied without direct interference from the laser. The shock wave formed at early times exhibits properties typical of both hydrodynamic and electrostatic shocks, including ion reflection. At late times, the shock is seen to evolve into a hydrodynamic blast wave. [ABSTRACT FROM AUTHOR]

This work developed a novel method for the determination of N-methyl morpholine N-oxide (NMMO) in the solution of biorefining, such as lyocell or biomass pretreatment. Copper hydride in situ (CuH) was generated in alkaline solution from sodium borohydride and cupric ion to completely reduce NMMO to N-methyl morpholine (NMM). Finally, the generated volatile NMM was analyzed by headspace gas chromatography. The generation of in situ CuH, complete reduction of NMMO, and the gas–liquid equilibration of NMM can be synchronously completed at 80 °C in 30 min, with a cupric ion concentration of 20 μmol, sodium hydroxide (0.8 mmol), sodium borohydride (3.0 mg), and 1.0 mL 30% ammonium hydroxide in 5.0 mL aqueous solution. The lowest limit of NMMO quantification was 42 mg/L in the present method, with good precision (standard deviation = 5.62%) and accuracy (recoveries from 95.9 to 106%). The present method has high accuracy, sensitivity, and throughput. It should be a useful tool to determine the content of NMMO and allow optimize the cost efficiency. [ABSTRACT FROM AUTHOR]

Reduction of a dicopper(II) bis(hydroxide) complex with silanes in the presence of external copper or silver cations results in the formation of multinuclear hydride clusters, which were characterized by a variety of NMR spectroscopic experiments and X‐ray crystallography. In particular, the pentanuclear complexes adopt an unusual planar "bow tie" configuration. The copper hydride complexes are efficient catalysts for the dehydrogenation of formic acid to H2 and CO2. [ABSTRACT FROM AUTHOR]

Copper hydride compounds have attracted interest in diverse fields as base metallic material in place of rare and noble metals, which have widely been utilized in hydrogenation catalysts, hydrogen storage, and electrochemical materials. Since the first report on the synthesis of copper hydride complex [Cu6H6(PPh3)6] in 1971, copper hydride reagents have been utilized in a variety of organic transformation. While well‐characterized copper hydride complexes have been long limited to a few examples, recently several research groups have reported the synthesis of phosphine‐stabilized copper hydride complexes with various metal‐frameworks and unique reactivity. Here we review recent progress on the synthesis and structures of copper hydride complexes supported by phosphine ligands, including di‐, tri‐, and tetraphosphines, and also describe their reactivity with CO2. [ABSTRACT FROM AUTHOR]

We report mechanistic studies on the insertion reactions of [(NHC)Cu(μ‐H)]2 complexes with carbonyl substrates by UV‐vis and 1H NMR spectroscopic kinetic studies, H/D isotopic labelling, and X‐ray crystallography. The results of these comprehensive studies show that the insertion of Cu‐H with an aldehyde, ketone, activated ester/amide, and unactivated amide consist of two different rate limiting steps: the formation of Cu‐H monomer from Cu‐H dimer for more electrophilic substrates, and hydride transfer from a transient Cu‐H monomer for less electrophilic substrates. We also report spectroscopic and crystallographic characterization of rare Cu‐hemiacetalate and Cu‐hemiaminalate moieties from the insertion of an ester or amide into the Cu−H bond. [ABSTRACT FROM AUTHOR]

The encapsulation of copper inside a cyclodextrin capped with an N‐heterocyclic carbene (ICyD) allowed both to catch the elusive monomeric (L)CuH and a cavity‐controlled chemoselective copper‐catalyzed hydrosilylation of α,β‐unsaturated ketones. Remarkably, (α‐ICyD)CuCl promoted the 1,2‐addition exclusively, while (β‐ICyD)CuCl produced the fully reduced product. The chemoselectivity is controlled by the size of the cavity and weak interactions between the substrate and internal C−H bonds of the cyclodextrin. [ABSTRACT FROM AUTHOR]