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ABSTRACT A detailed mechanistic investigation of the Zn (II)‐catalyzed Csp–Csp2 (Sonogashira‐type) cross‐coupling reaction is reported herein, using the Density Functional Theory method. The present study unveiled an unconventional non‐redox mechanism for Zn‐catalyzed cross‐coupling reaction, where the oxidation state of Zn remains intact throughout the catalytic cycle. Our study further revealed the significant role of the base in controlling the feasibility of cross‐coupling reactions that are catalyzed by electron‐deficient metal centers. Our study indicates that K3PO4 acts as an ancillary ligand (Lewis base) for the electron‐deficient Zn (II) catalytic center rather than as a proton abstractor for the nucleophilic coupling partner (phenylacetylene) in this reaction. The active catalyst was identified to be a four‐coordinate bis‐DMEDA Zn (II) complex. The mechanism proceeds via the initial activation of the nucleophilic coupling partner (phenylacetylene), followed by the electrophilic coupling partner (organic halide) activation liberating the cross‐coupled product by a concerted nucleophilic substitution pathway. The turn‐over limiting step was identified to be the activation of the electrophilic coupling partner. The activation barrier obtained for the reaction, 31.0 kcal/mol concords well with experimental temperature requirements (125°C). The coordination by base is found to stabilize the rate‐determining intermediates and transition states involved in the reaction. The mechanistic insights gained from this study could aid in the rational design and development of sustainable cross‐coupling reactions using zinc as the catalyst. [ABSTRACT FROM AUTHOR]

Cyclic organic carbonates are defined as key compounds for a sustainable chemical economy. Their synthesis from CO2 under mild conditions is a useful way to valorise this greenhouse gas as carbon source. Even if a wide range of catalysts were described to promote the carbon dioxide cycloaddition into epoxides, only few ones concern enzymatic systems. The zinc–l‐histidine active site of carbonic anhydrase inspired the present work, pointing out that the imidazole moiety of the amino acid ligand has a crucial role. An extensive study was undertaken to establish the structure–activity relationship of imidazole derivatives, zinc salts, and their respective catalytic activity in the CO2 cycloaddition reaction. The effect of aromatic, alkyl, or iodine substituents and their position in N‐heterocycles were highlighted. A synergic effect was noted when combining imidazole compounds with zinc salts. The optimization of reaction conditions emphasised the in situ ZnI2–1‐methylimidazole catalytic system, which is selective toward cyclic styrene carbonates and efficient under solvent‐free mild conditions (50 °C, atmospheric CO2 pressure). Once reusing tests confirmed the catalytic system robustness, the reaction scope was enlarged to several epoxides resulting in 84%–99% yields of their corresponding cyclic carbonates. [ABSTRACT FROM AUTHOR]

Polycaprolactone (PCL) is a highly regarded biodegradable and environmentally friendly material that is extensively researched and applied in the field of biomedicine due to its exceptional biodegradability, biocompatibility, and other advantageous properties. The monomer ε-Caprolactone (ε-CL) plays a critical role in the synthesis of PCL, making it a key focus of study. This paper describes the preparation of hydrotalcite HT-Zn and SBA-15 through simple synthetic methods, and the subsequent creation of a hydrotalcite/SBA-15 composite catalyst, named HT-Zn/SBA-15, through a post-generation approach combining hydrotalcite and SBA-15. Scanning electron microscopy (SEM), wide-angle X-ray diffraction (XRD), and infrared spectroscopy (FT-IR) were employed to analyze the structures of the synthesized materials. The catalytic effects in Baeyer–Villiger oxidation were then investigated to examine the impact of various catalysts, solvents, and reaction conditions. The results indicated that utilizing HT-Zn/SBA-15 as the catalyst, acetonitrile as the solvent, and H2O2 as the oxidant, led to a conversion rate of cyclohexanone exceeding 80% and a selectivity of ε-CL surpassing 90% under the ideal reaction conditions. Additionally, the catalyst demonstrated excellent reusability, being able to be reused up to six times. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, contains a variety of articles on topics such as photocatalysts, Li-ion batteries, biofilm removal, and synthesis of different compounds. The document is a contents list for the journal's October 14, 2024 issue. The first paper discusses the synthesis and anti-cancer activity of acetals of arjunolic acid, while the second paper explores the hybridization of magnetic MOF composites with 3D terminal carboxyl hyperbranched polymers for dye wastewater treatment. The third entry is a correction to a previous article on fluorescence imaging of cellular GSH and the hindering influence of rutin on ferroptosis. [Extracted from the article]

A new series of 6‐methoxy‐2‐naphthalene based pyrimidinones were synthesized via one pot‐three component synthetic reaction of aryl aldehydes, 6‐methoxy‐2‐acetonapthone and urea in the presence of nano zinc ferrite catalyst under conventional method. The synthesized compounds were characterized by their spectral techniques including FT‐IR, H1, C13 NMR, LCMS, and analysis of elements. Molecular docking analysis was also performed to identify the protein‐ligand interactions and binding energy of synthesized compounds. Biological studies of all synthesized pyrimidinone compounds have been measured against bacterial and fungal strains by calculating the zone of inhibition. [ABSTRACT FROM AUTHOR]

The document is the contents list for an issue of the journal Chemical Communications. It includes the titles and authors of various articles and communications related to chemistry research. Topics covered include the potential of MOF-based single-atom photocatalysts, anion-exchange membrane electrolyzers for hydrogen production, and progress on lithium-sulfur batteries. The journal is published by The Royal Society of Chemistry, a leading chemistry community. [Extracted from the article]

An efficient and practical method was developed for the synthesis of C2‐symmetric 2,2′‐bipyridine‐α,α′‐1‐t‐butyl‐diol ligands. The disclosed synthesis involves the Ullmann homocoupling of a keto bromo‐pyridine under NiCl2/Zn/PPh3 conditions, followed by the stereoselective double hydrogen transfer to the obtained 2,2′‐bipyridine‐diketone using RuII Noyori–Ikariya catalysts. This approach allowed the successful synthesis of 2,2′‐bipyridine‐α,α′‐1‐t‐butyl‐diol, i.e (S,S)‐Bolm's ligand, with a quantitative yield and an excellent stereoselectivity (ee>99.5 %, de>99.5 %), with an overall yield of 69 % from easily accessible starting materials. [ABSTRACT FROM AUTHOR]

Here, the Zn/titanosilicate-1 (TS-1) catalysts with different loadings and promotors were prepared to investigate catalytic performance in the dehydrogenation of propane. Derived from the alteration of the strength and distribution of acid sites due to the variation of the ZnO loadings, the optimal catalytic activity and selectivity of 2Zn/TS-1 catalyst (2 wt% ZnO) can be well reasonably attributed to the appropriate number of acid sites and the acidic strength. The addition of promoters such as 0.5 wt% MgO and 2.0 wt% ZrO2 may improve the stability of Zn/TS-1 catalyst due to the strong interaction between Zn2+ and promoter ions, which is believed to partially prevent the reduction of Zn2+ to metallic Zn. 2Zn/TS-1 catalyst exhibited good recycle stability. The loss of active Zn species on the used catalysts can be suppressed by regeneration treatment in air, in which the interaction between the Zn2+ and TS-1 support could become stronger. Well dispersed titanosilicate-1 (TS-1) supported ZnO catalysts were prepared, among which 2Zn/TS-1 catalyst exhibited good catalytic performance and recycle stability. [ABSTRACT FROM AUTHOR]

Bimetallic Mn 99.3 Zn 0.7 -MOF-74 with the highest ratio of MnIII exhibited efficient performance for the direct oxidative carboxylation of olefins to cyclic carbonates under mild and solvent-free conditions using aqueous TBHP oxidant, and could be reused for 5 consecutive runs without significant loss in activity and structure. [Display omitted] • In the obtained bimetallic MnZn-MOF-74, the valance state distributions of Mn were regulated with different Zn amount. • High ratio of active MnIII as main oxidant centers and Lewis acid/base sites made Mn 99.3 Zn 0.7 -MOF-74 catalyst efficient. • On direct oxidative carboxylation of styrene, Mn 99.3 Zn 0.7 -MOF-74 provided 92% styrene conversion with 59.8% selectivity. • Mn 99.3 Zn 0.7 -MOF-74 presented great universality to various olefins substrates and could be reused consecutively 5 runs. Multi-functional MOF catalyst with oxidative- and acid- centers showed potential in olefins oxidative carboxylation to cyclic carbonates directly. In this work, a series of bimetallic MnZn-MOF-74 with different molar ratios of Mn and Zn were synthesized successfully through a one-pot facile method. Thoroughly characterization indicated that the existence of Zn regulated the valance state distribution of Mn in the obtained MnZn-MOF-74. Mn 99.3 Zn 0.7 -MOF-74 with the highest ratio of MnIII (61.3 %) performed the most efficient activity for olefin direct tandem oxidative carboxylation reaction using aqueous tert -butyl hydroperoxide oxidant under solvent-free condition of 90 °C, 1.0 MPa CO 2 and 4 h. Mn 99.3 Zn 0.7 -MOF-74 also showed satisfactory versatility and recyclability. Based on the experiments, a feasible mechanism was presented. Thanks to the high ratio of active MnIII as main oxidative center, the coordination unsaturated bimetal Mn and Zn as Lewis-acid sites, O2– of metal − O as Lewis-base sites and combined effect with Bu 4 NBr cocatalyst, Mn 99.3 Zn 0.7 -MOF-74 presented efficient performance for the direct synthesis of cyclic carbonates from olefins. The metal Zn in MOF can regulate the valance state distribution of Mn and result in efficient catalytic property, presenting a potential avenue for direct oxidative carboxylation reaction of olefins to cyclic carbonates synthesis. [ABSTRACT FROM AUTHOR]

With the increasing levels of CO2 emissions and the decreasing availability of energy resources, the electrocatalytic CO2 reduction reaction (CO2RR) offers a promising method for utilizing CO2 as a valuable resource using sustainable electrical energy. However, developing cost‐effective and highly efficient catalysts remains a significant challenge. Although zinc, an abundant element on Earth, has shown potential for converting CO2 into CO, its effectiveness as a catalyst for CO2 reduction is hindered by its low selectivity and stability. This study introduces a fast, efficient, and simple electrochemical deposition method for preparing porous zinc nanosheets (NS) using the hydrogen bubble template approach. The as‐prepared zinc NS catalyst demonstrates exceptional catalytic activity due to its highly porous structure and high specific surface area. At a voltage of −1 V versus RHE, it achieves a maximum CO Faradaic efficiency of 89.5 %. The performance of this system is characterized by a partial current density of around −6.17 mA cm−2 in an H‐cell configuration. Additionally, our catalyst exhibits remarkable durability over 10 h, highlighting its significant potential for real‐world utilization in CO2RR. [ABSTRACT FROM AUTHOR]

The document is the contents list for the journal "Chemical Communications" published on September 25, 2024. It includes various articles on topics such as responsive DNA hydrogels, lithium metal-based battery systems, and strategies in photochemical alcohol oxidation. The journal is published by The Royal Society of Chemistry, a leading chemistry community, and aims to connect the world with the chemical sciences. [Extracted from the article]

Electrocatalytic nitrate reduction reaction (NO3RR) coupled with organic compounds to synthesize oximes for value-added conversion of waste pollutants has very promising prospects. However, due to the susceptibility of the feedstock to hydrogenation, the relatively low reaction efficiency, and the poor stability of oximes, the reaction in acidic electrolytes remains a formidable challenge. Herein, we report a novel strategy for the one-step synthesis of oximes from nitrite and aldehydes/ketones in acidic electrolytes using a Zn-based catalyst (multilayered Zn nanosheet catalyst, M-ZnNSs). 99% yield and 99% selectivity of phenylacetaldehyde oxime were achieved at a constant current of -12 mA cm-2. Moreover, various aldehydes/ketones were efficiently converted to oximes with yield and selectivity up to >90%, demonstrating the high versatility of this method. Furthermore, the catalyst exhibited remarkable long-term stability (>100 h). This work proposes a green strategy to promote the recycling of nitrogen resources, enhance the value of NO3- conversion products, and develop new ideas for electrochemical C-N coupling. [ABSTRACT FROM AUTHOR]

Glycolysis of waste polyethylene terephthalate (PET) is a green and high-value PET recovery approach, the product of which can be used as raw materials to prepare polyurethanes. Enhancing the conversion rate and monomer selectivity of PET glycolysis through the development of efficient catalysts is crucial for reducing both the energy consumption and operational costs associated with the process. In this study, a series of deep eutectic solvents (DESs) were synthesised based on L-proline (Pro) and its derivatives and used as catalysts for the glycolysis of PET using 1,4-butanediol (BDO). Under the optimized reaction conditions (5.0 g PET, 25.0 g BDO, 2 wt% Pro/Zn(Ac)2 catalyst, 210 °C, 15 min and atmospheric pressure), PET was degraded completely, and the yield of monomeric bis(4-hydroxybutyl)terephthalate (BHBT) reached 67.1%. Based on the results of in situ-IR, ¹H NMR and density functional theory (DFT), the possible catalytic mechanism of DESs synergistically promoting PET depolymerization was proposed. Finally, aromaticbased polyurethane elastomers (PUEs) were prepared with PET glycolysis products bis(2-hydroxyethyl) terephthalate (BHET) and BHBT as chain extenders. Compared with the control group, the thermal and mechanical properties of aromatic-based PUEs were improved, which proved the feasibility of high value utilization of PET glycolysis products. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes various articles on topics such as COF solid-state electrolytes for lithium batteries, supramolecular light-harvesting systems, functional surfactant-directing ultrathin metallic nanoarchitectures, recent advances in radical cyclization, and more. The journal is published by The Royal Society of Chemistry and focuses on exceptional research in the field of chemistry. [Extracted from the article]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes various articles on topics such as responsive theranostic agents, cationic ligands, green synthesis of zeolite, and transition metal oxide clusters. The journal is published by The Royal Society of Chemistry and focuses on connecting the world with the chemical sciences. The document provides a comprehensive overview of the articles included in the journal issue. [Extracted from the article]

Advanced oxidation processes (AOP) stood out as an efficient alternative for the treatment of organic contaminants. In this work, there were proposed syntheses of mixed catalysts of pyrite and graphene oxide and pyrite and zinc oxide to treat a mixture of the drugs atenolol and propranolol in aqueous solution through the photo-Fenton process with ultraviolet radiation. The efficiency of the methodologies used in the syntheses was confirmed through different characterization analyses. It was verified that the pyrite and zinc oxide catalyst led to the best contaminant degradation percentages with values equal to 88 and 84% for the groups monitored at the wavelengths (λ) of 217 and 281 nm. The degradation kinetics presented a good fit to the kinetic model proposed by Chan and Chu (2003) with R2 equal to 0.99, indicating a pseudo-first-order degradation profile. Finally, toxicity tests were carried out with two types of seeds, watercress and cabbage, for the solution before and after treatment. The cabbage seeds showed a reduction in germination percentages for the samples after treatments, while no toxicity was observed for watercress ones. This highlights the importance of evaluating the implications caused by products in relation to different organisms representing the biota. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes highlights, feature articles, and communications on various topics related to chemistry. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The contents list provides a range of research articles on topics such as catalysts, perovskites, photoluminescence, and electrocatalysis. [Extracted from the article]

New and simple ligand design strategies for the preparation of versatile metal-based catalysts capable of operating under greener and eco-friendly conditions in several industrially attractive processes are in high demand for society development. We present the first nucleophilic addition of an organolithium to ketenimines which incorporates a stereogenic centre in an N-donor atom to prepare new enantiopure NNN-donor scorpionates. We have also verified its potential utility as a valuable scaffold for chirality induction through the preparation of inexpensive, non-toxic and asymmetric zinc complexes. The pro-ligands and the corresponding zinc-based complexes have been characterized by X-ray diffraction studies. DFT studies were carried out to rationalize the different complexation abilities of these pro-ligands. These complexes have proved to act as highly efficient catalysts for a variety of sustainable bioresourced processes that are industrially attractive, with a wide substrate scope. Thus, complex 7 behaves as a highly efficient initiator for the well-behaved living ring-opening polymerization (ROP) of rac-lactide under very mild conditions. The PLA materials produced exhibited enhanced levels of isoselectivity, comparable to the highest value reported so far for zinc-based catalysts (Pi = 0.88). In addition, the combination of 7 with onium halide salts functioned as a very active and selective catalyst for CO2 fixation into five-membered cyclic carbonates through the cycloaddition of CO2 into epoxides under very mild and solvent-free conditions, reaching very good to excellent conversions (TOF = 227 h−1). Furthermore, this bicomponent system exhibits a broad substrate scope and functional group tolerance, including mono- and di-substituted epoxides, as well as the very challenging bio-renewable tri-substituted terpene-derived cis/trans-limonene oxide, whose reaction proceeds with high stereoselectivity. Finally, complex 7 also achieved high activity and selectivity as a one-component initiator for the synthesis of poly(cyclohexene carbonate)s via ring-opening copolymerization (ROCOP) of cyclohexene oxide and CO2 under very soft conditions, affording materials with narrow dispersity values. [ABSTRACT FROM AUTHOR]

Formaldehyde (HCHO) is a common indoor air pollutant. Due to its proven carcinogenicity, reducing indoor HCHO levels is a significant issue. In this study, a composite material consisting of zinc manganese oxide and BiVO4 was used as a photocatalyst for HCHO degradation. ZnMn2O4‐BiVO4 has efficient photocatalytic performance, wide application areas, high stability, and low‐cost advantages, making the substance a potentially useful photocatalyst that can be applied in fields such as energy conversion and environmental protection. BiVO4 was prepared by a hydrothermal method. It was further compounded with zinc manganese oxide to form composite as catalysts of different wt % ratios for photodegradation of HCHO using a fluorescent lamp as light source. The samples were characterized by using XRD, UV‐visible spectrometer, TEM, SEM, and photoluminescence spectrometry. The experimental data showed that 5.0 wt % zinc manganese oxide‐BiVO4 as catalyst had the highest HCHO degradation rate. The release of carbon dioxide and water increased the irradiation time. The degradation rate of HCHO was higher than that achieved with commercially available titanium oxide. The highest HCHO degradation rate was 66 % within 4 h. [ABSTRACT FROM AUTHOR]

Electrochemical nitrate reduction reaction (NitRR) uses nitrate from wastewater, offering a hopeful solution for environmental issues and ammonia production. Yet, varying nitrate levels in real wastewater greatly affect NitRR, slowing down its multi‐step process. Herein, a multi‐strategy approach was explored through the design of ordered mesoporous intermetallic AuCu3 nanocorals with ultrathin Au skin (meso‐i‐AuCu3@ultra‐Au) as an efficient and concentration‐versatile catalyst for NitRR. The highly penetrated structure, coupled with the compressive stress exerted on the skin layer, not only facilitates rapid electron/mass transfer, but also effectively modulates the surface electronic structure, addressing the concentration‐dependent challenges encountered in practical NitRR process. As expected, the novel catalyst demonstrates outstanding NitRR activities and Faradaic efficiencies exceeding 95 % across a real and widespread concentration range (10–2000 mM). Notably, its performance at each concentration matched or exceeded that of the best‐known catalyst designed for that concentration. Multiple operando spectroscopies unveiled the catalyst concurrently optimized the adsorption behavior of different intermediates (adsorbed *NOx and *H) while expediting the hydrogenation steps, leading to an efficient overall reduction process. Moreover, the catalyst also displays promising potential for use in ammonia production at industrial‐relevant current densities and in conceptual zinc‐nitrate batteries, serving trifunctional nitrate conversion, ammonia synthesis and power supply. [ABSTRACT FROM AUTHOR]

The model precatalyst sp3- and sp2-N dinitrogen-coordinated zinc–heteroimidazole has been used as an efficient catalyst for the ring-opening polymerization of cyclic esters. Subsequent to our exceptional active 5,6,7-trihydroquinolin-8-amine-zinc catalysts for the ring-opening polymerization (ROP) of ε-caprolactone, various pyridine-fused cycloalkanones (ring size from five to eight) are developed for the correspondent fused amine–pyridine derivatives and their zinc–heteroimidazole chloride complexes Zn1–Zn8 (LZnCl2) bearing N-diphenylphosphinoethyl pendants. Activated with two equivalents of LiN(SiMe3)2, the title zinc complexes efficiently promote the ROP of L-lactide (L-LA) in situ; among them, Zn4/2Li(NSiMe3)2 catalyzed 500 equivalent L-LA at 80 °C with 92% conversion in 5 min (TOF: 5520 h−1). Under the same conditions, the catalytic efficiency for the ROP of rac-LA by Zn1–Zn8/2Li(NSiMe3)2 was slightly lower than that for L-LA (highest TOF: 4440 h−1). In both cases, cyclooctyl-fused pyridyl–zinc complexes exhibited higher activity than others, while the cycloheptyl-fused zinc complexes showed the lowest activity. The microstructure analysis of the polymers showed they possessed a linear structure capped with CH3O as major and cyclic structure as minor. In this work, all the ligands and zinc complexes were well characterized by 1H/13C/31P NMR, FT-IR spectroscopy as well as elemental analysis. [ABSTRACT FROM AUTHOR]

It was crucial to develop a catalyst with high catalytic activity at low temperatures, as the zinc‐based catalysts were prone to deactivation in the high‐temperature reaction of acetylene acetoxylation, and Ionic liquid (IL)‐silver (Ag) catalysts were synthesized and applied in acetylene acetoxylation. The X‐ray diffraction, transmission electron microscopy, and X‐ray photoelectron spectroscopy characterizations displayed that Ag species were stabilized in the state of Ag+, and the dispersion of the Ag active species was effectively improved in supported‐ionic‐liquid‐phase (SILP) system. Furthermore, we prepared Ag‐IL liquid phase catalysts for catalyzing acetylene acetoxylation in liquid phase systems. It was demonstrated that the presence of ILs could effectively stabilize the Ag+ active site. The catalytic performance of the Ag‐IL/AC catalyst prepared in this article at a low temperature of 180 °C was 2.5 times that of the traditional Zn/AC catalyst. The development of low‐temperature catalysts would play a driving role in the development of acetylene acetoxylation. [ABSTRACT FROM AUTHOR]

A zinc‐catalyzed C(sp2)−N dehydrative cross‐coupling between carboxylic acids and NH‐sulfoximines to afford N‐aroylated sulfoximines under mild reaction conditions is described. Various NH‐sulfoximines were coupled with readily available carboxylic acids to provide the corresponding N‐aroylated sulfoximines in good to excellent yields. [ABSTRACT FROM AUTHOR]

This document is a contents list for the New Journal of Chemistry, a publication by The Royal Society of Chemistry. It provides information about the journal's editorial, cover image, and articles featured in the current issue. The articles cover a wide range of topics in chemistry, including electrodeposition, supercapacitors, catalysis, and photocatalysis. Some specific papers discussed include the bactericidal effects of zeolitic imidazolate frameworks, the use of nanoparticle-decorated glyceryl monostearate as a targeted drug carrier, and the construction of S@C composites for Mg-S batteries. Other papers explore topics such as metal-organic framework-derived bimetallic oxides as anode materials for lithium-ion batteries, advancements in protection of steel surfaces using polystyrene supported nanoparticles, and the enhancement of vanadium dioxide for supercapacitor applications. The document also includes papers on coordination chemistry, synthetic approaches for coumestan derivatives, and the design of metal complexes for targeting breast cancer. [Extracted from the article]

The Faraday efficiency of CO 2 electroreduction to CO catalyzed by metalloporphyrins (MTPP, M = Fe, Co, Cu, Zn and Ni) is linearly related to the reaction energy barrier of the first proton-coupled electron reduction. [Display omitted] • Five metalloporphyrins(MTPPs) with different metal centers are compared for CO 2 RR. • CO 2 RR mechanism on MTPPs are calculated by first-principles calculations. • CoTPP exhibits the best CO 2 RR activity and selectivity. • The results of theoretical calculation are well verified by experimental tests. • The linear correlation between the selectivity of CO and the key energy barrier is revealed. Metal-functionalized porphyrin-like graphene structures are promising electrocatalysts for carbon dioxide reduction reaction (CO 2 RR) as their metal centers can modulate activity. Yet, the role of metal center of metalloporphyrins (MTPPs) in CO 2 reaction activity is still lacking deep understanding. Here, CO 2 RR mechanism on MTPPs with five different metal centers (M = Fe, Co, Cu, Zn and Ni) are examined by first-principles calculations. The *COOH formation is the rate determined step on the five MTPP structures, and the CoTPP exhibits the best CO 2 RR activity while ZnTPP and NiTPP are the worst, which is also verified by our experiment. The CO 2 RR activity is controlled by adsorption states of intermediates (*CO, *COOH), i.e., chemisorption (e.g., on CoTPP) and physisorption (on ZnTPP and NiTPP) of intermediates will lead to good and poor activity, respectively. The deeper the d- band center of the porphyrin ring complexed metal atom, the weaker bonding of MTPP with CO and COOH. Theoretical calculations and experimental results indicate that MTPPs with Co and Fe centers lead to a reduction in the energy barriers for the two uphill reaction steps in the electrocatalytic CO 2 reduction process, thereby enhancing CO 2 reduction electrocatalytic activity. Faradaic efficiency of CO is correlated with the reaction energy barrier of the first proton-coupled electron reduction process, displaying a strong linear correlation. This work provides a fundamental understanding of MTPPs used as electrocatalysts for CO 2 RR. [ABSTRACT FROM AUTHOR]

In this study, the magnetic Mg0.5Zn0.375Ni0.125Fe2O4 nanoparticle was prepared by the co-precipitation method and characterized with various methods, such as FT-IR, XRD, TGA, FESEM, EDX, and VSM. The catalytic activity of this magnetic nanocatalyst was perused in synthesizing dihydropyrano[2,3-c] pyrazole and tetrahydrodipyrazolopyridines derivatives. To indicate some of this paper's preponderances, preparing a novel heterogeneous magnetic nanocatalyst with high reactivity produces high-yield and purity products. Moreover, the synthesized nanocatalyst has advantages such as high catalytic activity, non-toxicity, short reaction time, easy separation from the reaction mixture using an external magnet, and reusability several times without significant loss in its catalytic activity. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, contains a variety of articles on different topics in chemistry. The articles cover areas such as polydimethylsiloxane coatings, water oxidation, lithium-ion batteries, and photocatalytic reactions. The journal provides valuable insights for those interested in chemistry and covers a diverse range of research areas. The document is a list of research papers published in the journal Chemistry in 2024, including topics such as the electrocatalytic degradation of tetracycline, the construction of a supramolecular system for imaging nematic mesophase and nematode cells, insights into hydrogen bond strengths in microhydrated clusters, and the development of macrophage-red blood cell hybrid membranes for eliminating pathogens, endotoxins, and heavy metal ions from blood. [Extracted from the article]

A series of tri-coordinated zinc alkyl complexes with the general molecular formula [κ2NE-{NHIRP(Ph)(E)N-Dipp}ZnEt] [R = Dipp (2,6-diisopropylphenyl), E = S (3a), Se (3b) and R = tBu (tert-butyl), E = S (4a), Se (4b)] bearing imino-phosphanamidinate chalcogenide ligands were prepared in good yields from the reaction between the protic imino-phosphanamidinate chalcogenide ligand [NHIRP(Ph)(E)NH-Dipp] [R = Dipp, E = S (1a), Se (1b) and R = tBu, E = S (2a), Se (2b)] and diethylzinc at room temperature. The molecular structures of all the zinc complexes were established by single-crystal X-ray diffraction analysis. In the solid state, all complexes exhibited a distorted trigonal planar geometry around the zinc ion. Metal-chalcogenide (Zn–S/Se) interactions were observed in the coordination sphere. These zinc alkyl complexes were employed as pre-catalysts in the hydroboration reaction of nitriles and esters to obtain the corresponding N,N-diborylamines and boronate esters, respectively, under ambient conditions. A wide substrate scope of nitriles and esters is presented. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The privileged C2‐symmetric rigid phenol‐type ligand is more attractive but challenging in asymmetric catalysis. Herein, we designed and synthesized a class of rigid‐featured chiral tridentate Phenol‐2NO ligands, that incorporate the advantages of both the phenol skeleton and pyrroloimidazolone‐based N‐oxide moiety, from readily available L‐prolinamides in operationally simple two steps and up to 44% overall yield. More importantly, using an achiral quinoline derivative as an additive, the newly developed Phenol‐2NO ligand could serve as the anioic ligand upon deprotonative activation to coordinate to Zn(II) to form a highly enantioselective catalyst for the asymmetric Michael‐type Friedel‐Crafts alkylation reaction of indoles with 2,3‐dioxopyrrolidines. Excellent yields (up to 90%) and high enantioselectivities (up to 99% ee) are obtained for a wide range of substrates under mild conditions. Experiments and DFT calculations revealed the reaction mechanism and the origins of the enantioselectivity. This also represented the first activation of phenol‐type ligand/metal complex by an achiral organic base as the additive in asymmetric catalysis. [ABSTRACT FROM AUTHOR]

Fluoroalkyl groups play an irreplaceable role in the field of pharmaceutical and agrochemical industry due to their unique properties. Based on this, it is crucial to effectively introduce fluoroalkyl groups into target molecules. In this review, we describe the synthesis of well‐defined fluoroalkyl zinc complexes and their applications in the fluoroalkylation of compounds. Different from the reactivities of copper fluoroalkyl complexes, fluoroalkyl zinc complexes often needed to be combined with copper or nickel catalysts when participating in fluoroalkylation reactions. From the perspective of reaction mechanism, the transfer of trifluoromethyl from zinc complexes to copper catalysts formed the highly active trifluoromethyl copper reagents, which can be directly used for the fluoroalkylation. In most cases, the desired target products were provided with excellent yields. [ABSTRACT FROM AUTHOR]

The impact of aluminum trialkyl (AlR3) and esters/silane-external electron donor (EED) on the activity and reaction kinetics of ZN catalyst (TiC14//MgCl2—ethyl benzoate/diisobutyl phthalate) in propylene polymerization was studied. The polymerization kinetic was studied for different types of catalysts with various types of EEDs. To correlate the kinetic behavior of propylene polymerization and various reactions taking place during the polymerization, we have studied in situ interactions of EEDs with co-catalyst by FT-NMR. The used EEDs are (1) p-isopropoxy methyl benzoate (PIPMB), (2) diphenyldimethoxy silane (DPDMS) and (3) mixture of isopropyl myristate (IPM) and (DPDMS) were interacted with triethyl aluminum (TEAl) at defined molar ratios. In the diester type of catalyst, two types of kinetic profile were observed with two different types of EED systems. Initially very fast polymerization kinetic was observed when only silane type of EED was used during polymerization which became steady with mixed EED (Silane + Aliphatic Ester). This EED system shows steady-state and controllable kinetic characteristics due to mixing of IPM with silane. The study by FT-NMR spectroscopy indicated the formation of the new compounds that are inhibiting the rate of polymerization reaction. The compounds, such as ketones and alcohols, are responsible for controlling the rate of polymerization reaction. The contribution of each of these product formations during processes depends on the catalyst composition and on the polymerization conditions. [ABSTRACT FROM AUTHOR]

In recent times, the research on the synthesis of highly functionalized piperidines has become a challenge and an attractive research field among synthetic chemists because these compounds have many biological, pharmaceutical and industrial applications. In this regard, in this paper we would like to report a green, rapid and efficient method for the synthesis of highly functionalized piperidines based on the use of zinc (II) chloride supported on Fe3O4 NPs modified with Dopamine and 5H-Cyclopenta[2,1-b:3,4-b′]dipyridin-5-one [Fe3O4@Dop/CP-diPy-ZnCl2 as a novel magnetically reusable catalyst. The structure of Fe3O4@Dop/CP-diPy-ZnCl2 nanocatalyst was well identified by several spectroscopic techniques including: FT-IR, TEM, SEM, EDX, ICP-OES, TGA, XRD, VSM and Elemental mapping technique. One-pot three-component reactions of aromatic amines with different aryl aldehydes and β-ketoesters were performed in water and all desired highly functionalized piperidines were synthesized with high to excellent yields, which indicates the high efficiency of this catalytic system. The reusability tests shown that that Fe3O4@Dop/CP-diPy-ZnCl2 catalyst is a reusable and stable catalyst. [ABSTRACT FROM AUTHOR]

Formaldehyde-water-trioxane (HCHO–H2O–TOX) tends to form a stable azeotrope and the HCHO solution can also produce multiple by-products, making it challenging to refine and obtain high-purity TOX, resulting in increased energy consumption. Formic acid (FA) is the most easily generated and undesirable main byproduct of HCHO, which has strong corrosiveness to production equipment. However, the negative impact of HCHO mentioned above is often overlooked because of its low concentration. In this study, the CuO/ZnO–AlN catalyst was synthesized using a simple deposition precipitation method. The catalyst demonstrated a high removal rate of HCHO and inhibition of FA, along with excellent hydrothermal stability. Aluminum nitride (AlN) can form a layer of Al(OH)3 coating, acting as a physical barrier against H2O during the reaction process and releasing trace OH− to facilitate the formation of Cannizaro intermediates. It can then catalyze HCHO dehydrogenation under alkaline-free conditions to form H2 and an intermediate (HCOO−), which is further converted to H2 and CO2 under the influence of Cu0. The relevant characterization results showed that Cu0 is the active site. The strong interaction between AlN and copper refines the particle size of CuO and promotes the reduction of CuO to Cu0. In addition, an H2 atmosphere can more effectively inhibit the oxidation of Cu0 compared to an N2 atmosphere, resulting in a higher HCHO removal rate. This rate can reach 100% at 105 ℃ and 4 MPa H2 and almost no FA can be detected in the product. Cycling tests proved that the prepared catalyst could be recycled and reused three times without a noticeable reduction in catalytic activity, demonstrating its good application potential. [ABSTRACT FROM AUTHOR]

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation (PDH). In this work, an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH catalyst. Defect engineering is applied to induce the formation of defective porous silicalite-1 (DPS-1), which is favorable for achieving the uniformly distributed ZnO nanoclusters. The ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt atoms. The structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the DPS-1. Moreover, the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH process. As expected, the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance (propane conversion of 40.7%, propylene selectivity of 97.5%) and good cycling regeneration stability. This work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes various articles on topics such as catalyst design for carbon nanotubes, hydrogen bond types, DNA aptamer molecules, plutonium peroxides, and C-H alkylation. The journal is published by The Royal Society of Chemistry and focuses on connecting the world with the chemical sciences. [Extracted from the article]

At present, under the background of the excess product oil market, "reducing oil products and increasing chemical raw materials" has become the mainstream trend in the chemical industry. In recent years, ZSM-5 zeolite catalyst has been widely used in the aromatization of FCC gasoline, but its modification to improve its aromatization catalytic performance is still not perfect. Therefore, based on the existing process technology, the effect of pseudo-boehmite on the aromatization performance of Zn-P-Al/ZSM-5 catalysts was investigated on a small continuous fixed-bed reactor using 75-120 °C fractions of FCC gasoline as feedstock. The results show that the aromatization performance of Zn-P-Al/ZSM-5 catalyst is better than that of Zn-P/ZSM-5 and HZSM-5, and the best aromatization performance is obtained when the pseudo-boehmite ratio is 30%, the aromatics content and aromatics yield in liquid products are 90.82% and 54.38%, respectively. The results of catalyst characterization are consistent with those of catalyst evaluation. [ABSTRACT FROM AUTHOR]

In this study, Co/Ni‐NC catalyst with hetero‐diatomic Co/Ni active sites dispersed on nitrogen‐doped carbon matrix is synthesized via the controlled pyrolysis of ZIF‐8 containing Co2+ and Ni2+ compounds. Experimental characterizations and theoretical calculations reveal that Co and Ni are atomically and uniformly dispersed in pairs of CoN4‐NiN4 with an intersite distance ≈0.41 nm, and there is long‐range d–d coupling between Co and Ni with more electron delocalization for higher bifunctional activity. Besides, the in situ grown carbon nanotubes at the edges of the catalyst particles allow high electronic conductivity for electrocatalysis process. Electrochemical evaluations demonstrate the superior ORR and OER bifunctionality of Co/Ni‐NC catalyst with a narrow potential gap of only 0.691 V and long‐term durability, significantly prevailing over the single‐atom Co‐NC and Ni‐NC catalysts and the benchmark Pt/C and RuO2 catalysts. Co/Ni‐NC catalyzed Zn–air batteries achieve a high specific capacity of 771 mAh g−1 and a long continuous operation period up to 340 h with a small voltage gap of ≈0.65 V, also much superior to Pt/C‐RuO2. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 to methanol with H2 from renewable energy has attracted increasing interest as a promising strategy for reducing excessive CO2 emissions. However, the performance of reported various catalysts still suffers from low methanol yield with a passable CO2 conversion. In this work, Cu–ZnO–La2O3 interfaces are constructed with various La2O3 mole ratio. Compared to Cu/ZnO, the optimized catalyst (i.e., Cu0.6Zn0.2La0.4) exhibits a much higher mass-specific methanol formation rate (159.3 gMeOH/kgcat/h) at 240 °C and 3 MPa. A series of ex-situ and in-situ characterizations, such as X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), N2O titration measurements, and in-situ diffuse reflectance Fourier transform infrared spectroscopy (in-situ DRIFTS) study, are used to investigate its structure and mechanism study. The dispersion of Cu over Cu/ZnO/La2O3 catalyst is significantly enhanced, forming more Cu–ZnO–La2O3 interfaces. LaOx species favor CO2 activation and generate more carbon intermediates species for CO2 hydrogenation. Furthermore, more Cu+ is bonded, which stabilizes the key intermediate, inhibits its desorption, and facilitates its further hydrogenation to methanol. This work is expected to offer an effective strategy to develop new catalysts with high performance for CO2 hydrogenation to methanol. [ABSTRACT FROM AUTHOR]

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Iron‐nitrogen‐carbon (Fe‐N‐C) single‐atom catalysts are promising sustainable alternatives to the costly and scarce platinum (Pt) to catalyze the oxygen reduction reactions (ORR) at the cathode of proton exchange membrane fuel cells (PEMFCs). However, Fe‐N‐C cathodes for PEMFC are made thicker than Pt/C ones, in order to compensate for the lower intrinsic ORR activity and site density of Fe‐N‐C materials. The thick electrodes are bound with mass transport issues that limit their performance at high current densities, especially in H2/air PEMFCs. Practical Fe‐N‐C electrodes must combine high intrinsic ORR activity, high site density, and fast mass transport. Herein, it has achieved an improved combination of these properties with a Fe‐N‐C catalyst prepared via a two‐step synthesis approach, constructing first a porous zinc‐nitrogen‐carbon (Zn‐N‐C) substrate, followed by transmetallating Zn by Fe via chemical vapor deposition. A cathode comprising this Fe‐N‐C catalyst has exhibited a maximum power density of 0.53 W cm−2 in H2/air PEMFC at 80 °C. The improved power density is associated with the hierarchical porosity of the Zn‐N‐C substrate of this work, which is achieved by epitaxial growth of ZIF‐8 onto g‐C3N4, leading to a micro‐mesoporous substrate. [ABSTRACT FROM AUTHOR]

The reaction between bis(1,2,3‐triazol‐1‐yl)methane derivatives and nBuLi and various aldehydes, yielded novel neutral ligand precursors incorporating alcohol functional groups. The resulting compounds exhibited distinct characteristics depending on the steric hindrance of the aldehyde employed. In instances where aromatic aldehydes were utilized, functionalization occurred at the methine group bridging both triazole rings. Conversely, the use of pivalic aldehyde prompted functionalization at the C5 position of the triazole ring. These compounds were subsequently employed as ligand precursors in the synthesis of organometallic aluminum and zinc complexes, yielding dinuclear complexes with high efficiency. The structural elucidation of all compounds was accomplished through spectroscopic methods and validated by X‐ray crystallography. Preliminary catalytic investigations into the coupling reaction of cyclohexene oxide and CO2 revealed that aluminum and zinc complexes catalyzed the selective formation of polyether and polycarbonate materials, respectively. [ABSTRACT FROM AUTHOR]

This study is the first application of a PVDF-HFP-based polymer inclusion membrane incorporating the poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and di(2-ethylhexyl)phosphoric acid (D2EHPA) as the base polymer and extractant for the extraction of bismuth(III), respectively. It is demonstrated that the PIM comprised of 60 wt% PVDF-HFP and 40 wt% D2EHPA is the most effective in the extraction of bismuth(III) from feed solution containing 20 mg L−1 bismuth(III) and 0.2 mol L−1 sulfate adjusted to pH 1.4. The extracted bismuth(III) ions are back-extracted quantitatively to the receiving solution containing 1 mol L−1 sulfuric acid. The stoichiometry experiments reveal that the Bi: D2EHPA ratio in the bismuth(III) extracted complex is 1:6, and D2EHPA is dimer. Moreover, it is shown that the studied PIM has high selectivity in the extraction of bismuth(III) over other interfering ions such as Mo(VI), Cr(III), Al(III), Fe(III), Ni(II), Zn(II), Cd(II), Co(II), Cu(II), and Mn(II). The interference of Fe(III) is also eliminated by masking with fluoride, leading finally to a nearly pure extraction of bismuth(III). [ABSTRACT FROM AUTHOR]

Herein we report a sustainable approach for the alkylation of ketones, 9H‐fluorene, oxindole, and indole using alcohols as the alkylating agent catalyzed by a well‐defined air‐stable zinc catalyst (1 a) of a tridentate redox non‐innocent arylazo ligand, 2‐((4‐chlorophenyl)diazenyl)‐1,10‐phenanthroline (La). 2–3 mol % of 1 a efficiently produces substituted α‐alkylated ketones, 9‐alkylated fluorenes, C3‐alkylated oxindoles, and C3‐alkylated indoles in moderate to good isolated yields. In aerial condition, the formation of bis(indolyl)methane (BIMs) derivatives were observed when indoles were subjected to alkylation by primary alcohols. A few drug molecules containing BIMs were prepared in good isolated yields. The catalyst 1 a exhibited good chemoselectivity during the functionalization of fluorene and indole with oleyl alcohol and β‐citronellol. A few control experiments, including deuterium labeling experiments, performed to unveil the reaction mechanism indicate that the one‐electron reduced azo‐anion radical species [1 a]‐formed in situ, acts as the active catalyst. All the redox events occur at the redox‐active aryl‐azo ligand, which acts as the reservoir of hydrogen and electrons throughout the catalytic cycle, keeping the Zn(II)‐center as a template. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal Chemical Communications, published by The Royal Society of Chemistry. It includes articles on various topics such as photocatalytic production of hydrogen peroxide, metal-organic frameworks as solid-state electrolytes for lithium batteries, and the redox noninnocence of a phenothiazine-substituted borane. The journal aims to connect the world with the chemical sciences and invest its profits back into the chemistry community. [Extracted from the article]

Le Chatelier's principle is a basic rule in textbook defining the correlations of reaction activities and specific system parameters (like concentrations), serving as the guideline for regulating chemical/catalytic systems. Here we report a model system breaking this constraint in O2 electroreduction in mixed dioxygen. We unravel the central role of creating single-zinc vacancies in a crystal structure that leads to enzyme-like binding of the catalyst with enhanced selectivity to O2, shifting the reaction pathway from Langmuir-Hinshelwood to an upgraded triple-phase Eley-Rideal mechanism. The model system shows minute activity alteration of H2O2 yields (25.89~24.99 mol gcat−1 h−1) and Faradaic efficiencies (92.5%~89.3%) in the O2 levels of 100%~21% at the current density of 50~300 mA cm−2, which apparently violate macroscopic Le Chatelier's reaction kinetics. A standalone prototype device is built for high-rate H2O2 production from atmospheric air, achieving the highest Faradaic efficiencies of 87.8% at 320 mA cm−2, overtaking the state-of-the-art catalysts and approaching the theoretical limit for direct air electrolysis (~345.8 mA cm−2). Further techno-economics analyses display the use of atmospheric air feedstock affording 21.7% better economics as comparison to high-purity O2, achieving the lowest H2O2 capital cost of 0.3 $ Kg−1. Given the recent surge of demonstrations on tailoring chemical/catalytic systems based on the Le Chatelier's principle, the present finding would have general implications, allowing for leveraging systems "beyond" this classical rule. The principle of Le Chatelier is a fundamental concept in textbooks, serving as a guiding principle for controlling chemical and catalytic systems. In this study, the authors present an oxygen electroreduction system based on a single zinc vacancy catalyst, which operates in a manner that extends "beyond" Le Chatelier's principle. [ABSTRACT FROM AUTHOR]