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Azo compounds with a high density, high enthalpy, and excellent detonation performance have received increasing research attention. The conventional method of chemical dehydrogenation that is used to form azo compounds involves the use of strong oxidants, resulting in environmental pollution. Electrochemical organic synthesis is considered an old method and a new technology. In this work, azofurazan tetrazole {H2 AzFT; 5,5′-[diazene-1,2-diylbis(1,2,5-oxadiazole-4,3-diyl)]bis-1 H -tetrazole} and azofurazan hydroxytetrazole (H2 AzFTO) were synthesized by a green and efficient electrochemical dehydrogenation coupling of 5-(4-aminofurazan-3-yl)-1 H -tetrazole and 5-(4-aminofurazan-3-yl)-1-hydroxytetrazole, respectively. The structures of H2 AzFT and (NH4)2 AzFTO were fully characterized by infrared spectroscopy, nuclear magnetic resonance, and elemental analysis, and their thermal stabilities were determined by differential thermal analysis. [ABSTRACT FROM AUTHOR]

ABSTRACT Ionic liquids (ILs) have been recognized for their potential as environmentally friendly solvents when compared to traditional organic solvents. Additionally, their function goes beyond that of solvents, and cocatalysts, as they frequently act as stabilizing agents and ligands for the metal‐active species and intermediates in catalytic systems. This comprehensive review primarily focuses on the application of Pd‐incorporated ILs in catalyzing cross‐coupling Suzuki reactions. The responses play a vital role in creating a wide range of structurally diverse and highly functionalized organic compounds, focusing specifically on nucleopalladation Suzuki coupling reactions. The review provides a detailed summary of the reaction conditions, stereoselectivity and regioselectivity, and the underlying mechanisms. Furthermore, it underscores crucial and characteristic illustrations, displaying the practical implementations of these coupling reactions. The aim of this review is to stimulate further research efforts, with the ultimate goal of expanding our understanding and utilization of ILs in various fields in the future. [ABSTRACT FROM AUTHOR]

Photolysis of phenacyl benzoates tethered with a phenol or anisole in acetone resulted in the formation of 1,4‐dicarbonyl compounds, coupling products of the phenacyl moiety with acetone. The reaction occurs via electron and/or proton transfer from a triplet exciplex, leading to the formation of a phenacyl radical, which then adds to the enol form of acetone. The reaction also occurs in intermolecular fashion with external electron donors. [ABSTRACT FROM AUTHOR]

Modular synthesis can combine different functional modules to flexibly regulate comprehensive properties and study the diversity of compounds. This study established a modular bicyclic synthesis strategy of combining polynitro energetic module with iodine‐containing biocidal module. Compounds 1–6 with high iodine content (48.72–69.56 %) and high thermal stability (Td: 172–304 °C) were synthesized and exhaustively identified. By modular synthesis, the detonation properties and gas‐production of 3–6 improved greatly expanding their biocidal efficacy and maintained the iodine atomic utilization of iodine‐containing module. Notably, 4,5‐diiodo‐3,4',5'‐trinitro‐1,3'‐bipyrazole (5) and 3,5‐diiodo‐4,4',5'‐trinitro‐1,3'‐bipyrazole (6) exhibit high detonation velocities (D: 5903 m s−1, 5769 m s−1, respectively) and highest gas production of 212.85 L mol−1 and 217.66 L mol−1 after decomposition. This study diversifies polyiodio‐nitro compounds, and also inspire the implementation of similar synthesis strategies to provide family‐level synthetic solutions to energetic biocidal materials. [ABSTRACT FROM AUTHOR]

Copper immobiolized onto the polyvinyl imidazole coated magnetic graphene oxide [MGO@PVimCu(I)] was synthesized and characterized by various analytical methods such as FT-IR, XRD, TGA, TEM, FESEM, VSM and ICP-OES. According to the FE-SEM and TEM results, the size of the snared nanoparticles in the polymer matrix was about 50–90 nm and the surface of the catalyst was rough. The loading percentage of copper onto the polyvinyl imidazole coated MGO was determined to be 17% using ICP-OES, which is far better than the many known metal-based heterogeneous catalysts. In the catalytic activity scrutiny, A3 coupling reaction for the preparation of propargylamines and coupling reaction of aryl halides with nucleophiles were aimed. In the presence of MGO@PVimCu(I), the corresponding products were gained in these reactions with moderate to excellent yields in aqueous medium (50–99%). This method demonstrates several considerable benefits including product yields, the use of various substrates, easy work-up, separation of catalyst by a simple external magnet, reusability of catalyst (at least four cycles), eco-friendliness, and avoidance of using any toxic solvent. The results of this study have shown that this catalyst can be a suitable candidate for other organic transformations. [ABSTRACT FROM AUTHOR]

Combining hydrogen evolution with the conversion of benzyl alcohol (BA) into benzaldehyde (BAD) could provide an alternative pathway for sufficiently utilizing photogenerated electrons and holes to achieve high value chemicals and fuels. Herein, a ZnIn2S4 nanosheet array/one-dimensional Co9S8 hollow nanotube (Co9S8/ZnIn2S4) composite has been fabricated by simple hydrothermal and solvent thermal methods. Without the utilization of sacrificial agents, the optimal 20%-Co9S8/ZnIn2S4 hybrid catalyst shows a superior H2 production of 3070.56 μmol·g–1·h–1 and a high benzyl alcohol conversion rate of 93.2%, which are 4.1 and 2.9 times higher than those of individual ZnIn2S4, respectively. The superior photocatalytic performance over Co9S8/ZnIn2S4 nanocomposites compared with bare ZnIn2S4 can be credited to the introduction of Co9S8 hollow nanotubes as a cocatalyst, which can offer plentiful active sites, improve the absorption of visible light, and facilitate the separation and transfer of electron–hole pairs of ZnIn2S4. Multiple cycling experiments indicate good durability of the Co9S8/ZnIn2S4 nanocomposite. In addition, the in situ electron paramagnetic resonance indicates that α-hydroxybenzyl radicals are the key intermediate of the conversion of BA into BAD. This paper is intended to provide a meaningful reference for the ingenious design of the photocatalyst structure and building a high-performance coupled photocatalytic system with sufficient utilization of electrons and holes. [ABSTRACT FROM AUTHOR]

Conversion of CO2 into high‐value chemicals using solar energy is one of promising approaches to achieve carbon neutrality. However, the oxidation of water in the photocatalytic CO2 reduction is kinetically unfavorable due to multi‐electron and proton transfer processes, along with the difficulty in generating O−O bonds. To tackle these challenges, this study investigated the coupling reaction of photocatalytic CO2 reduction and selective propane oxidation using the Pd/P25 (1 wt%) catalyst. Our findings reveal a significant improvement in CO2 reduction, nearly fivefold higher, achieved by substituting water oxidation with selective propane oxidation. This substitution not only accelerates the process of CO2 reduction but also yields valuable propylene. The relative ease of propane oxidation, compared to water, appears to increase the density of photogenerated electrons, ultimately enhancing the efficiency of CO2 reduction. We further found that hydroxyl radicals and reduced intermediate (carboxylate species) played important roles in the photocatalytic reaction. These findings not only propose a potential approach for the efficient utilization of CO2 through the coupling of selective propane oxidation into propylene, but also provide insights into the mechanistic understanding of the coupling reaction. [ABSTRACT FROM AUTHOR]

An efficient catalytic asymmetric dearomatizing amination of 2-naphthols and phenols catalyzed by N,N′-dioxide-copper(I) complex as a chiral catalyst was presented. A variety of optically active β-naphthalenone compounds with a nitrogen-containing quaternary carbon stereocenter were obtained with high yield and enantioselectivity under mild reaction conditions. Mechanistic studies indicated that this Csp2–N dearomatizing coupling proceeds via 1,3-reductive elimination of phenolate-CuIII-amino intermediate in five-membered ring transition states. The origin of enantioselectivity has also been elucidated based on density functional theory calculations. [ABSTRACT FROM AUTHOR]

The coupling of the carbon dioxide reduction reaction (CO2RR) and methanol oxidation reaction (MOR) holds great promise for the energy‐efficient production of HCOO−. However, anode catalysts' limited selectivity (<80%) and stability (<15 h) have impeded electron utilization and HCOO− production rates. To overcome it, copper‐copper(I) oxide‐copper(II) oxide nanowires (Cu─CuO─Cu2O NWs) catalysts have been developed, which exhibit exceptional performance in promoting the MOR with a faradic efficiency of nearly 100% at commercially viable current densities, and long stability over 100 h at 100 mA cm−2. Interestingly, the unique structure of the catalysts, when exposed to methanol, facilitates a transition from Cu/CuO to Cu2O. This phenomenon promotes the MOR while inhibiting the competitive oxygen evolution reaction (OER). By coupling the anodic reaction with cathodic CO2 reduction, the system demonstrates exceptional performance in HCOO− production, achieving an overall faradic efficiency of nearly 200% at 100 mA cm−2 with a low cell voltage of 2.382 V. Techno‐economic analysis indicates that the production costs of HCOOH are ≈US$0.37 and 0.35 kg−1 at 100 and 150 mA cm−2, respectively, significantly lower than those associated with traditional electrochemical methods. [ABSTRACT FROM AUTHOR]

New phenylacetic acid derivatives with potentially valuable biological activities and the ability to act as starting materials for various functionalizations have been prepared by a multi-step synthesis. Starting from 2,6-dibromo-4-methylaniline, the synthetic route involves the construction of the basic aromatic structure (3,4,5-triphenyltoluene) (two steps), followed by its conversion into 2-[(3,4,5-triphenyl)phenyl]acetic acid and derivatives (up to five steps). Based on this multi-step synthesis, five compounds not previously reported in the literature were synthesized; the literature-known 3,4,5-triphenyltoluene was synthesized for the first time in the manner described. This synthesis is applicable for the preparation of numerous new representatives of this class of compounds. [ABSTRACT FROM AUTHOR]

Carbon‐11 (11C) is a widely used radionuclide for positron emission tomography (PET) owing to the omnipresence of carbon atoms in organic molecules. While its half‐life of 20.4 min is ideal for imaging and dosimetry, it also limits the synthetic possibilities. As such, the development of fast and easy, high‐yielding synthesis methods is crucial for the application of 11C‐labeled tracers in humans. In this study, we present a novel and efficient method for the reaction of [11C]CO2 with amine precursors using benzotriazole‐1‐yl‐oxy‐tris‐(dimethylamino)‐phosphonium hexafluorophosphate (BOP) to access 11C‐labeled ureas. Our method is extremely fast as it only requires transfer of [11C]CO2 into a solution with precursor and BOP at room temperature, where it reacts momentary into the desired 11C‐labeled urea. This simple procedure makes it possible to radiolabel urea directly from [11C]CO2 without the need for advanced equipment, making the method applicable for all laboratories where [11C]CO2 is available. We synthesized a small series of aliphatic symmetrical and non‐symmetrical 11C‐labeled ureas using this method, and achieved good to excellent yields. The novelty of our study lies in the fact that peptide coupling reagent BOP is used for the first time in radiochemistry to activate [11C]CO2, facilitating its reaction with amines to obtain 11C‐labeled ureas. [ABSTRACT FROM AUTHOR]

A convenient Cu(I) Catalyzed three‐component coupling strategy for the synthesis of polysubstituted pyrroles is developed using simple and readily available building blocks like, 1, 3‐dicarbonyl compound, aryl amine, and β‐nitrostyrene. CuI has been rarely explored for the pyrrole ring synthesis and a comparative analysis of our current catalyst with a range of previously reported catalysts suggested that, CuI is one of the best catalysts for the multicomponent synthesis of polysubstituted pyrrole derivatives. Notably, this process has several advantages, including a simple and practical set‐up with hassle free reaction conditions, extensive substrate scope, short reaction time, high atom economy and environmentally favorable approach. This methodology provides an alternative approach to the highly substituted pyrroles and under optimized reaction conditions, polysubstituted pyrroles were formed in good to excellent yields. Cu(I) catalyzed Mannich reactions followed by Michael addition reactions along with subsequent intramolecular cyclization are believed to be the key steps of this reaction process. [ABSTRACT FROM AUTHOR]

A new procedure for the synthesis of novel ketonitrones has been developed. The procedure involves the coupling of Grignard reagents with the easily accessible and stable N-substituted α-(1H-benzotriazol-1-yl) nitrones in the presence of catalytic amounts of zinc bromide. [ABSTRACT FROM AUTHOR]

Previous studies reported that hemoprotein CYP450 catalyzed triclosan coupling is an “uncommon” metabolic pathway that may enhance toxicity, raising concerns about its environmental and health impacts. Hemoglobin, a notable hemoprotein, can catalyze endogenous phenolic amino acid tyrosine coupling reactions. Our study explored the feasibility of these coupling reactions for exogenous phenolic pollutants in plasma. Both hemoglobin and hemin were found to catalyze triclosan coupling in the presence of H₂O₂. This resulted in the formation of five diTCS-2 H, two diTCS-Cl-3 H, and twelve triTCS-4 H in phosphate buffer, with a total of nineteen triclosan coupling products monitored using LC-QTOF. In plasma, five diTCS-2 H, two diTCS-Cl-3 H, and two triTCS-4 H were detected in hemoglobin-catalyzed reactions. Hemin showed a weaker catalytic effect on triclosan transformation compared to hemoglobin, likely due to hemin dimerization and oxidative degradation by H₂O₂, which limits its catalytic efficiency. Triclosan transformation in the human plasma-like medium still occurs with high H₂O₂, despite the presence of antioxidant proteins that typically inhibit such transformations. In plasma, free H₂O₂ was depleted within 40 minutes when 800 µM H₂O₂ was added, suggesting a rapid consumption of H₂O₂ in these reactions. Antioxidative species, or hemoglobin/hemin scavengers such as bovine serum albumin, may inhibit but not completely terminate the triclosan coupling reactions. Previous studies reported that diTCS-2 H showed higher hydrophobicity and greater endocrine-disrupting effects compared to triclosan, which further underscores the potential health risks. This study indicates that hemoglobin and heme in human plasma might significantly contribute to phenolic coupling reactions, potentially increasing health risks.

This communication describes a highly recyclable, ecologically friendly, ionic liquid catalyst supported by cobalt that is active in the Suzuki-Miyaura reaction at 70 ​°C. To be more precise, the procedure is initiated with a special form of the ecologically safe solvent 3-(2-aminoethyl)-1-methyl-1H-imidazole-3-ium bromide [Aemim]Br. A few benefits of the coupling process include its simplicity of use, broad range of substrate compatibility with high yields, environmental friendliness, high reaction rate, low catalyst loading (0.001 ​mol%), and recyclability (up to 7 cycles).

Owing to the environmental and energy problems nowadays, one of the enormous challenges is expanding clean, renewable energy to reduce the destructive ecological effects of chemical industries. Compared with other traditional processes, the electrochemical method has some benefits, such as being selective, causing minor waste, and working under mild conditions with no external oxidizing or reducing reagents, making this approach more economical and eco-friendly. Electrochemistry represents a powerful tool within synthetic organic chemistry. The development part of chemistry intends the performance of organic reactions employing electrons, including adding or removing electrons. Using electric current as a reagent has some advantages, such as simplicity of reactions, accessibility of materials, replacing toxic oxidizing or reducing reagents, and applying an eco-friendly environment. During the last decades, there has been much effort to decrease the usage of fossil fuels, and electricity has emerged as a common energy source. The conversion of electricity energy into chemical energy leads to new synthetic paths, and this energy is naturally safe and environmentally friendly. Developing electrochemistry approaches for performing high-performance organic reactions is essential for chemical industries. The electrochemical reaction is a green strategy because of the utilization of electric current instead of stoichiometric oxidants or reductants. Due to its helpful and environmentally friendly ability to produce reactive intermediates, organic electrochemistry has advanced considerably in oxidative hydrogen evolution coupling and sacrificial anode electroreduction. New developments in organic electrochemistry focus on developing new electrolytic catalysts,photoelectrocatalysis, bioelectrosynthesis, optimizing electrode materials, paired electrolysis, and artificial intelligence-assisted electrosynthesis. Thus, organic electrochemistry is expanding daily because of the significant number of construction projects and the possibilities of applying organic electrochemistry. Electrochemical methods for constructing organic compounds have tolerated renewal for the past decades. Organic electrochemistry has a wealthy background in organic synthesis. We hope this review helps to attract more attention to organic electrochemistry from researchers by using electrochemical processes in the laboratory and the industrial centers, which decrease pollution and create an eco-friendly. In this review, the electrochemical coupling reaction of organohalides for synthesizing various coupling products has been summarized and discussed since 2000.

The acylation of bromobenzene with 3-(4-bromophenyl)-3-chlorophthalide gave 3,3-bis(4-bromo-phenyl)phthalide which was used as a monomer to obtain poly(diphenylenephthalide) {poly(3-oxo-1H2-benzofuran-1,1-diyl[1,1′-biphenyl]-4,4′-diyl} by polycondensation via the Ni(0)-catalyzed coupling. The described reaction provides a new synthetic approach to poly(arylenephthalides). [ABSTRACT FROM AUTHOR]

In this paper, we present a one‐pot protocol that enables a straightforward and selective transformation of alkyl benzothiazol‐2‐yl and phenyltetrazol‐2‐yl sulfones and acyl chlorides into ketones, E‐olefins, Z‐olefins, and even pyrroles. The final product of the reaction depends on the proper choice of the reaction workup. Notably, the protocol designed for olefin formation allows a switch between E‐ and Z‐olefin formation by the correct choice of the reaction workup. These developed protocols facilitate the formation of all compounds under mild reaction conditions, as evidenced by the synthesis of (nitro)‐fatty acids, and the concept can be extended to other product formations, as demonstrated by the synthesis of pyrroles. [ABSTRACT FROM AUTHOR]

The injection of hydrogen-bearing additives, which markedly decrease coke consumption, calls for refinement of the equations describing chemical reactions in the blast furnace. In the last few decades, many researchers have studied the reaction of coke with atmospheres containing H2 and H2O. Tube furnaces are used for the laboratory study of such processes. As a rule, such systems permit automated gas supply, weighing of the samples, and determination of the exhaust gas composition in a gas analyzer. Analysis of the results indicates that, at the same temperature, the gasification of the carbon in coke is more intense in reactions with H2O than with CO2. [ABSTRACT FROM AUTHOR]

New phenylacetic acid derivatives with potentially valuable biological activities and the ability to act as starting materials for various functionalizations have been prepared by a multi-step synthesis. Starting from 2,6-dibromo-4-methylaniline, the synthetic route involves the construction of the basic aromatic structure (3,4,5-triphenyltoluene) (two steps), followed by its conversion into 2-[(3,4,5-triphenyl)phenyl]acetic acid and derivatives (up to five steps). Based on this multi-step synthesis, five compounds not previously reported in the literature were synthesized; the literature-known 3,4,5-triphenyltoluene was synthesized for the first time in the manner described. This synthesis is applicable for the preparation of numerous new representatives of this class of compounds.

Background: Particularly developed ingredients that are easily manufactured and utilized for additional exploitation are used in organic synthetic chemistry. Thionyl chloride serves as a significant illustration of such an ingredient. The usefulness of which has been discussed in a huge number of peer-reviewed papers. Aim: The literature that has been released since the previous assessment in 1980, which mainly focused on the responses of active methylene compounds, is where this review places its focus. In the present overview, we also discuss O- and N-nucleophiles. For the most part, patents have been disregarded in this analysis in order to keep it feasible. Conclusion: The authors concluded that SOCl2 has a variety of behaviors, including the ability to function as an initiator or a reactant, which makes it essential for the synthesis of many chemically reactive intermediates and final products. Additionally, SOCl2 can speed up and reduce the duration of traditionally long reactions, thereby raising its importance.

Olefins are a very important class of compounds, which can be transformed to various complex organic molecules through a series of transformations. In this paper, C―C cross coupling reaction based on olefinic C―H bond activation is described in detail. Based on the activation of C―H bonds, C―C bonds are constructed through C―C cross coupling reaction by transition metal catalysts such as Rh, Pd and Co. This introduction of olefinic C―H bond activation can enrich and expand the knowledge of olefins in organic chemistry courses, and it is also helpful for students to understand the forefront of organic chemistry development, stimulate their learning enthusiasm and initiative, and cultivate their scientific research literacy. [ABSTRACT FROM AUTHOR]

Palladium nanoparticles (PdNPs) have gained significant importance due to its prodigious properties and applications. To harness the multifaceted applications of PdNPs, we report a facile synthesis of calix[4]pyrrole tetrabenzohydrazide capped-Palladium nanoparticles (CPTBH-PdNPs) through a one-pot synthetic pathway. Comprehensive characterization using UV–Visible spectroscopy, Transmission Electron Microscopy (TEM), Selected Area Electron Diffraction (SAED), Energy-Dispersive X-ray, X-ray Diffraction, Zeta Potential, and Dynamic Light Scattering techniques confirmed the successful formation of CPTBH-PdNPs. These nanoparticles were employed as catalysts in Suzuki–Miyaura coupling reactions under mild conditions, resulting in efficient bond formations. Furthermore, the CPTBH-PdNPs exhibited remarkable anti-cancer effects against the human breast cancer cell line MDA-MB-231, with an IC50 value of 38.86 µg/mL. Additionally, the nanoparticles demonstrated exceptional efficacy against Mycobacterium tuberculosis, with a minimum inhibitory concentration (MIC) value of 0.8 µg/mL. These findings highlight the multidimensional nature of calix[4]pyrrole capped PdNPs and suggest their potential application as future materials in various fields. [ABSTRACT FROM AUTHOR]

The (S)‐nobin‐embodied picolinamide and L‐hydroxyproline‐derived amide are effective ligands for Cu‐catalyzed enantioselective coupling reaction of (hetero)aryl iodides with α‐alkyl substituted cyanoacetates. This arylation reaction gave α‐(heteroaryl)‐α‐alkyl cyanoacetates in good to excellent enantioselectivities (up to 95 % ee). A variety of functionalized (hetero)aryl and alkyl groups could be introduced to the quaternary center and therefore provided a valuable tool for preparing enantioenriched compounds with an all‐carbon quaternary center tethered with convertible functional groups. The size of both α‐alkyl and ester groups was proven as the key factor for asymmetric induction. [ABSTRACT FROM AUTHOR]

The coupling reaction between NH-sulfoximine and substituted toluene is achieved under mild conditions via visible light-catalysis strategy using easily prepared unprotected NH-sulfoximine with cheap and readily available substituted toluene as starting materials. After the effects of different photocatalysts, bases, and solvents in the reaction are investigated, substrate scopes of sulfoximines and toluene are expanded. Finally, preliminary studies on the antibacterial activity of the products are conducted. The results show that the optimal reaction conditions are： sulfoximine(0. 2 mmol), toluene(0. 24 mmol), potassium carbonate(0. 26 mmol), Eosin Y(0. 02 mmol), NBS(0. 26 mmol), isopropanol(1 mL), reaction at room temperature for 24 h under 18 W blue LED light. This reaction has good applicability to different sulfoximine substrates and toluene substrates, with yields ranging from 46% to 75%. Among the 16 tested compounds，7 compounds have inhibitory effects on Escherichia coli and 6 compounds have inhibitory effects on Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Based on Gaussian 16 software, the structures of reactants and products in diazotization and coupling reactions of p-aminobenzene sulfonic acid are studied using the B3LYP and B2PLYP methods in density functional theory. By calculation and simulation, the geometry and electron distribution of the reactants and products are optimized. The results show that the enthalpy change of the diazotization reaction is -117 kJ/mol, and the Gibbs free energy change is -160 kJ/mol. The enthalpy change of the coupling reaction is -484 kJ/mol, and the Gibbs free energy change is -460 kJ/mol, indicating that both diazotization and coupling reactions are exothermic and irreversible. The thermodynamic calculations of diazotization and coupling reactions of p-aminobenzene sulfonic acid provide a theoretical basis for controlling reaction process conditions and thermodynamic research. [ABSTRACT FROM AUTHOR]

Today, blast furnaces tend to operate with large quantities of injected materials—hydrogen sources. In the 1960s, the introduction of such additives prompted close attention to the chemical processes in the blast furnace. In the last few decades, many researchers have studied the reaction of coke with atmospheres containing H2 and H2O. This sharp increase in interest may be attributed to the increasing presence of hydrogen in blast furnaces and to the availability of powerful methods such as X-ray phase analysis and electron microscopy and also software for digital image analysis and thermodynamic analysis. The thermodynamic laws and kinetics of blast furnace processes were studied. The results show that coke reacts with H2O more intensely and with greater intensity than it reacts with CO2. That affects the coke strength. Other research has addressed the influence of the H2 and H2O content on the porosity of the coke and its disintegration. Recently, thermodynamic analysis of the gasification of carbon from coke in a CO2 + H2O atmosphere (solution loss reaction of coke) by various research groups shows that increase in the H2O content in the initial gas further stimulates gasification. Thermodynamic analysis of the reactions associated with the gasification of coke by CO2 and H2O and the reduction of iron oxides (the coupling reaction) indicates that higher hydrogen content in the gas may shift the gasification of carbon to lower temperatures. [ABSTRACT FROM AUTHOR]

A facile and efficient method to synthesize thioethers from sulfonyl chlorides and benzylic trimethylammonium salts is presented. This protocol provides a simple and direct approach to realize the reductive coupling reaction of readily available sulfonyl chlorides with benzyl ammonium salts in the presence of triphenylphosphine along with base via C−N cleavage of benzyl ammonium salts. This reaction features mild conditions and good substrate compatibility to afford thioethers in moderate to good yields. [ABSTRACT FROM AUTHOR]

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Indole alkaloids have attracted considerable attention from synthetic chemists and biochemists for their structural diversity and important biological activities. Compared with traditional organic synthesis methods, the strategy of using cytochrome P450s' extraordinary abilities to selectively activate carbon-hydrogen bonds to assist in the synthesis of various indole alkaloids has the characteristics of short synthetic route, mild conditions and high atomic economy. Here, we utilized P450 monooxygenases HinD and TleB to synthesize a novel 6/5/8 tricyclic product from (S)-N-((S)-1-(4-fluoro-1H-indol-3-yl)-3-hydroxypropan-2-yl)-2-mercapto-3-methylbutanamide through the substrate structure-directed strategy. TleB was more effective in catalyzing C–S coupling, and was used to synthesize a series of 6/5/8 tricyclic indololactam derivatives to provide drug candidates. Interestingly, the S–S coupling product was observed in HinD catalysis, which was a minor product in the wild-type TleB catalysis. With the help of protein engineering, we accurately regulated the catalytic flow and reversed the selectivity of TleB to obtain the S–S coupling product. At the same time, the reaction mechanism was reasonably speculated by means of site blocking and protein-substrate complex analysis. [ABSTRACT FROM AUTHOR]

Improving the aromatic selectivity in the alkane aromatization process is of great importance for its practical utilization but challenge to make because the high H/C ratio of alkanes would lead to a serious hydrogen transfer process and a large amount of light alkanes. Herein, CO2 is introduced into the cyclohexane conversion process on the HZSM-5 zeolite, which can improve the aromatic selectivity. By optimizing the reaction conditions, an improved aromatic (benzene, toluene, xylene, and C9+) selectivity of 48.2% can be obtained at the conditions of 2.7 MPa (CO2), 450 °C, and 1.7 h−1, which is better than that without CO2 (aromatic selectivity = 43.2%). In situ transmission Fourier transform infrared spectroscopy spectra illustrate that many oxygenated chemical intermediates (e.g., carboxylic acid, anhydride, unsaturated aldehydes/ketones or ketene) would be formed during the cyclohexane conversion process in the presence of CO2. 13C isotope labeling experimental results demonstrate that CO2 can enter into the aromatics through the formation of oxygenated chemical intermediates and thereby improve the aromatic selectivity. This study may open a green, economic, and promising way to improve the aromatic selectivity for alkane aromatization process. [ABSTRACT FROM AUTHOR]

Abstract Phenoselenazines are nitrogen and selenium-based heterocyclic compounds that have important biological activities. However, their preparation methods are scarce and difficult to handle. The synthesis of a phenoselenazine from a simple and robust CuO nanoparticle catalyzed methodology, using bis-aniline-diselenide and 1,2-dihalobenzenes under microwave irradiation. Also, the double-cross-coupling reaction mechanism for C-Se and C-N bond formation, including the observation of a reaction intermediate by mass spectrometry have been studied.

Industrial recovery of valuable elements in copper slag is the key to treat copper slag and protect the environment. However, the results of the industrial reduction of copper slag are not ideal at present, mainly because the oxidation problem caused by excess oxygen is not considered. In this study, the properties of three carbonaceous materials and the coupling reaction behavior of copper slag + C under CO2 atmosphere were investigated by thermogravimetric and thermokinetic analyses. The results showed the activity of the three carbonaceous materials to be in the order of coke > anthracite > coal. Coke was more conducive to the reduction of copper slag under Ar atmosphere, whereas anthracite was more conducive under CO2 atmosphere. The reduction amount and rate of copper slag under CO2 atmosphere were higher than those under Ar atmosphere within a certain temperature range. Moreover, the carbon burning loss increased significantly so that CO2 could re-oxidize the reduced metal elements after heating to 1300 ℃. The limiting steps of the reduction reaction of copper slag under Ar atmosphere mainly followed the three-dimensional diffusion (ZLT) model. On the other hand, under CO2 atmosphere, the limiting steps of some of the reactions changed due to the influence of the coupling reaction. Overall, we observed that the activation energies of the reduction and oxidation reactions under coupling conditions were higher.

Selective synthesis of specific value‐added aromatics from CO2 hydrogenation is of paramount interest for mitigating energy and climate problems caused by CO2 emission. Herein, we report a highly active composite catalyst of ZnZrO and HZSM‐5 (ZZO/Z5‐SG) for xylene synthesis from CO2 hydrogenation via a coupling reaction in the presence of toluene, achieving a xylene selectivity of 86.5 % with CO2 conversion of 10.5 %. A remarkably high space time yield of xylene could reach 215 mg gcat−1 h−1, surpassing most reported catalysts for CO2 hydrogenation. The enhanced performance of ZZO/Z5‐SG could be due to high dispersion and abundant oxygen vacancies of the ZZO component for CO2 adsorption, more feasible hydrogen activation and transfer due to the close interaction between the two components, and enhanced stability of the formate intermediate. The consumption of methoxy and methanol from the deep hydrogenation of formate by introduced toluene also propels an oriented conversion of CO2. [ABSTRACT FROM AUTHOR]

This paper provides a general overview of palladium complexes incorporating numerous multidentate azo-imine ligands, their structural diversity, synthetic protocol, interesting properties such as redox properties, biological activity and their further application on C – N coupling reactions, C – C cross-coupling reactions (e.g., Suzuki and Heck) and catalytic activity on different organic transformations. A detailed literature survey revealed that no brief review has yet been published on the azo-azomethine-based palladium complex. Therefore, the present review incorporates the research undertaken on the synthetic strategies and coordinating behaviour of various azo-imine ligands with palladium metal centre and a few important properties of metal complexes. [ABSTRACT FROM AUTHOR]

Cyclopropanols, due to their particular chemistry, can participate in various synthetic reactions with retention or cleavage of the strained three‐membered ring. Direct cross‐coupling ring‐opening reaction of such molecules access to organic compounds, such as ketones has great importance in medicinal chemistry and material sciences. Hence, the coupling reaction/cyclization ring‐opening of cyclopropanols for constructing new valuable molecules in the presence of a transition metal catalyst or under metal‐free conditions is described in this context. The features of the reactions are discussed, and the mechanisms of the challenging reactions are highlighted. [ABSTRACT FROM AUTHOR]

A green protocol for the in situ synthesis of Pd nanoparticles on chitosan beads (Pd NPs-CS) is reported without the need to use any toxic reducing agents. The preparation of the Pd nanoparticles catalyst was performed using a simple coordination reaction between the prepared chitosan beads and palladium ions (Pd NPs-CS). The obtained catalyst was characterized by different techniques, including SEM, EDX, DRX, and FTIR analyses. The Pd NPs-CS catalyst was investigated in the Suzuki–Miyaura cross-coupling reaction and Heck reaction under greener conditions, and the results show high catalytic activity and selectivity. The bead form of the Pd NPs-CS catalyst was easily separated from the reaction mixture to obtain the desired products, as confirmed by spectroscopic methods. This sustainable catalyst has the advantages of having sustainable organic reactions such as biopolymer support and recovery without significant loss of catalytic activity or selectivity. [ABSTRACT FROM AUTHOR]

Aryl nitriles, cyanation, coupling reaction, ligand, copper cyanide Remarkably, these reactions often proceed at relatively low temperatures and catalytic loadings in comparison with previous ligand-promoted Cu-catalyzed coupling reactions with (hetero)aryl halides. Keywords: aryl nitriles; cyanation; coupling reaction; ligand; copper cyanide EN aryl nitriles cyanation coupling reaction ligand copper cyanide 1395 1398 4 07/11/23 20230725 NES 230725 Graph Aryl nitriles have been frequently found in various drug molecules, dyes, and natural products. This result indicated that the active copper center coordinated with ligand might hinder I ortho i -substituted aryl bromide's approaching, showing a significant difference in reaction mechanism from the traditional Rosenmund-von Braun reaction. [Extracted from the article]

Design of solid‐supported metal catalysts (SSMCs) has made an increasingly important contribution to heterogeneous catalysis in terms of fundamental understanding and technological applications. For instance, industrial use of supported catalysts for oxidation, reduction, and C−C bond formation reactions is highly prevalent. The reason behind this is that such catalysts are economical, have high thermal stability, dispersion, high exposed surface area, and above all, high reusability (up to multiple subsequent cycles). Such characteristics make supported catalysts ideal for green synthesis. However, unlike homogeneous catalysis, heterogeneous catalysis is widely applied in crude oil refining, the pharmaceutical industry, water purification, natural product synthesis, and environmental catalysis. Carbon‐carbon bond formation reactions are frequently used in the organic synthesis using SSMCs. SSMCs are attractive to synthetic chemists due to their easy recovery and excellent stability compared to unsupported metal catalysts. However, the major drawback of SSMCs is related to metal sintering at elevated temperatures caused by weak interactions between the metal and solid support in SSMCs. This review highlights major advancements in SSMCs. Three commonly reported solid supports for metal catalysts, such metal oxides, carbonaceous materials, and polymeric compounds, are discussed. Moreover, a series of thermo‐ and photocatalyzed reactions, such as hydrogenation, carbon‐carbon bond formation, oxidation reactions and multicomponent reactions and the effect of variable supports towards activity and selectivity are demonstrated. [ABSTRACT FROM AUTHOR]

The catalytic conversions of CO2 into value added chemicals have attracted the interest of many visionary researchers. In this work, the coupling reaction of aziridine with CO2 has been investigated in the absence and presence of organocatalysts (TBD and 7-azaindole) computationally using density functional theory method. The kinetic and thermodynamic parameters of each mechanism were calculated at B3LYP/6-31G (d) level. The results show that, the TBD and 7-azaindole catalyzed reactions of aziridine with CO2 have significantly lower the energy barrier compared to a single step concerted non-catalyzed one. In TBD catalyzed reaction, mechanism I in which the TBD catalyst first interact with CO2 to form TBD-CO2 adduct (zwitterion) and then the zwitterion formed facilitated the ring opening of aziridine to form intermediate is the favorable path. In the case of 7-azaindole catalyzed reaction, mechanism 1 is the most favorable pathway in both gas phase and water phase. However, these parameters were significantly affected in the presence of water using Solvent Model Density (SMD). [ABSTRACT FROM AUTHOR]

A catalyst-free synthesis of phosphorothioates via a P–S cross-coupling reaction of thiols with dialkyl phosphites has been studied. With presented method, various phosphorothioates were obtained by the reaction of thiols with H-dialkyl phosphites in the presence of DMSO as both solvent and oxidant under transition-metal-free conditions. Mechanistic studies showed that the reaction proceeds with formation of a known disulfide intermediate via the oxidation of thiols in the presence of DMSO. Nucleophilic substitution of dialkyl phosphite with the disulfide intermediate gave phosphorothioate. The presented method is a convenient process for the synthesis of phosphorothioates under catalyst-free conditions. [ABSTRACT FROM AUTHOR]

The transition metal‐catalyzed cross‐coupling reaction with Fischer metal carbene intermediates bearing an electron‐rich alkoxyl or siloxyl group remains a big challenge due to the lack of readily available corresponding carbene precursors. Herein, we report the coupling of alkynes with the Fischer‐type copper carbene species bearing a α‐siloxyl group, which could be in situ generated from acylsilanes catalytically under photoirradiation and redox‐neutral conditions. The side‐arm modified bisoxazoline (SaBox) ligands prove to be crucial for this coupling reaction, which provides the corresponding alkynyl alcohol in high yields with remarkable heterocycle tolerance and broad substrate scope. [ABSTRACT FROM AUTHOR]

An unprecedented use of Mukaiyama reagent in the conversion of carboxylic acids into corresponding N-acyl benzotriazoles has been established with reliable and reproducible outcomes. Advantages associated with the developed method are easy handling, shorter reaction time, wide substrate scope and one-pot high-yielding reaction under mild conditions. Moreover, elimination of the column chromatography and use of green solvent make this procedure immensely useful for facile synthesis of N-acyl benzotriazole. [ABSTRACT FROM AUTHOR]

A rapid, effective, without transition metal and column chromatography-free protocol for the synthesis of 2,3-dihydroquinazolinones (DHQ) derivatives via one-pot tri-component reaction using amine, aldehyde (aromatic or aliphatic) and isatoic anhydride in the existence of Mukaiyama's reagent (CMPI: 2-chloro-1-methylpyridinium iodide) has been developed with commendable isolated yields. The operation is a high atom economy experimental procedure, with good functional group tolerance, broad substrate scope, and gives high yields in a short period. The trace metal contamination in synthesized pharmaceuticals is a big issue, the metal-free conditions is the highlighted advantage in solving this issue. [ABSTRACT FROM AUTHOR]

This review describes recent advances in copper-catalyzed difluoroalkylation reactions. The RCF2 radical is generally proposed in the mechanism of these reactions. At present, various types of copper-catalyzed difluoroalkylation reactions have been realized. According to their characteristics, we classify these difluoroalkylation reactions into three types. [ABSTRACT FROM AUTHOR]