Photoelectrocatalysis(PEC)is extensively applied in diverse redox reactions.However,the traditional oxygen evolution reaction(OER)occurring at the(photo)anode is hindered by high thermodynamic demands and sluggish kin...Photoelectrocatalysis(PEC)is extensively applied in diverse redox reactions.However,the traditional oxygen evolution reaction(OER)occurring at the(photo)anode is hindered by high thermodynamic demands and sluggish kinetics,resulting in excessive energy consumption and limited economic value of the O2 produced,thereby impeding the practical application of PEC reactions.To overcome these limitations,advanced anodic-cathodic coupling systems,as an emerging energy conversion technology,have garnered significant research interest.These systems substitute OER with lower potential,valuable oxidation reactions,significantly enhancing energy conversion efficiency,yielding high-value chemicals,while reducing energy consumption and environmental pollution.More importantly,by designing and optimizing photoelectrodes to generate sufficient photovoltage under illumination,meeting the thermodynamic and kinetic potential requirements of the reactions,and by tuning the voltage to match the current densities of the cathode and anode,coupling reactions can be achieved under bias-free conditions.In this review,we provide an overview of the mechanisms of PEC coupling reactions and summarize photoelectrode catalysts along with their synthesis methods.We further explore advanced catalyst modification strategies and highlight the latest development in advanced PEC coupling systems,including photocathodic CO_(2)reduction,nitrate reduction,oxygen reduction,enzyme activation,coupled with photoanodic organic oxidation,biomass oxidation,and pollutant degradation.Additionally,advanced in situ characterization techniques for elucidating reaction mechanisms are discussed.Finally,we propose the challenges in catalyst design,reaction systems,and large-scale applications,while offering future perspectives for PEC coupling system.This work underscores the tremendous potential of PEC coupling systems in energy conversion and environmental remediation,and provides valuable insights for the future design of such coupling systems.展开更多
Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annea...Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annealing process to stabilize nitrogen‐mesoporous carbon supported Pd single‐atom/cluster(Pd/NMC)material,which provided a catalyst with superior performance for Suzuki coupling reactions.In comparison with commercial palladium/carbon(Pd/C)catalysts,the Pd/NMC catalyst exhibited significantly boosted activity(100%selectivity and 95%yield)and excellent stability(almost no decay in activity after 10 reuse cycles)for the Suzuki coupling reactions of chlorobenzenes,together with superior yield and excellent selectivity in the fields of the board scope of the reactants.Moreover,our newly developed rapid annealing process of precursor solutions is applied as a generalized method to stabilize metal clusters(e.g.Pd,Pt,Ru),opening new possibilities in the construction of efficient highly dispersed metal atom and sub‐nanometer cluster catalysts with high performance.展开更多
Due to the increasing demand for the sustainability of modern organic chemistry, the development of green and powerful methods for C-C and C-B bond formation is highly desired. Among them, the transition-metal-free co...Due to the increasing demand for the sustainability of modern organic chemistry, the development of green and powerful methods for C-C and C-B bond formation is highly desired. Among them, the transition-metal-free coupling reactions of gem–diborylalkanes emerge as one valuable tool for organic chemists in the last decade. The review covers selected representative examples. A comparison of these reactions with transition-metal-catalyzed reactions is provided. The recent example of α-boryl radical formation from gem–diborylalkanes is also briefly discussed.展开更多
Binaphthalene-core phosphepine compounds with axial chirality belong to an important class of organocatalysts and ligands used in catalytic asymmetric synthesis.However,the number and application of these compounds ha...Binaphthalene-core phosphepine compounds with axial chirality belong to an important class of organocatalysts and ligands used in catalytic asymmetric synthesis.However,the number and application of these compounds have been limited due to the lack of efficient synthetic methods currently available to researchers.Herein,a simple and efficient palladium-catalyzed C—P cross-coupling reaction of enantiopure(R)-1 with a variety of aryl and heteroaryl halides is reported.The reaction provides access to a series of chiral binaphthalene-core phosphepine compounds using Pd(OAc)2/dippf as a catalyst,which allows most products to be formed in moderate to high yields(40%~92%)with excellent ee values(90%~99%ee).展开更多
Polyanilines(PANIs) can be easily prepared from the available and cheap anilines via the oxidative polymerization reactions. Owing to the coordination of nitrogen in the material with metals, PANIs are widely used as ...Polyanilines(PANIs) can be easily prepared from the available and cheap anilines via the oxidative polymerization reactions. Owing to the coordination of nitrogen in the material with metals, PANIs are widely used as the support of nano metal catalysts. In comparison with inorganic supports, the nano metals on PANIs were firmly anchored via the coordination bond so that they are not easily to lose during the reaction process. Moreover, since PANIs are versatile materials and their chemical features can be adjusted by introducing functional groups onto the monomers, the catalytic activities of the prepared catalysts are tunable. During the past decade, PANIs-supported nano metal catalysts have been widely applied in a variety of coupling reactions. This review aims to summarize the recent advances and give a perspective.展开更多
To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study invest...To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.展开更多
The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under ...The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under aerobic condition.This catalytic system demonstrates great tolerance to a wide range of groups on all substrates of aryl halides,alkenes and aryl boronic acids.展开更多
CuI/ethylene diamine/K2CO3/dioxane is shown to be a useful system for the cross coupling reactions of various aryl iodides and bromides with aryl and alkyl alkynes. Compared to the conventional Sonogashira reactions, ...CuI/ethylene diamine/K2CO3/dioxane is shown to be a useful system for the cross coupling reactions of various aryl iodides and bromides with aryl and alkyl alkynes. Compared to the conventional Sonogashira reactions, the new procedure is free of palladium and phosphines.展开更多
Sm/TiCl4 system could well integrate the high reactivity of samarium（Ⅱ） and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupl...Sm/TiCl4 system could well integrate the high reactivity of samarium（Ⅱ） and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupling reactions of ketones with esters mediated by metallic samarium （Sm） and a catalytic amount of titanium tetrachloride （TiCl4） were successfully developed. A series of substituted ketones and cyclic β-keto-esters were prepared in moderate to good yields under reflux and neutral conditions.展开更多
Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition...Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.展开更多
The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence...The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence that the perfect lattice sites on the anatase TiO2(001)-(1×4) surface are quite inert for the reaction of CH3CHO, but the reduced defect sites on the surface are active for the thermally driven reductive carbon-carbon coupling reactions of CH3CHO to produce 2-butanone and butene. We propose that the coupling reactions of CH3CHO on the anatase TiO2(001)-(1×4) surface should undergo through the adsorption of paired CH3CHO molecules at the reduced defect sites, since the existing reduced Ti pairs provide the suitable adsorption sites.展开更多
The application of atomically precise nanocluster-based catalysts in organic synthesis has been practiced for decades.Such nanoclusters have been used as ideal catalysts as their structures are designable at the atomi...The application of atomically precise nanocluster-based catalysts in organic synthesis has been practiced for decades.Such nanoclusters have been used as ideal catalysts as their structures are designable at the atomic level,their confined structures are conducive to mechanistic study,and most of them can be recycled during the synthesis process.The catalysis of coupling reactions using nanoclusters is an advanced methodology to build complicated carbohydrate scaffolds in one step.The history of atomically precise nanocluster-catalyzed coupling reactions is short;however,the past decade has witnessed the prosperity of this field-atomically precise nanocluster-catalyzed carbon–carbon coupling reactions including many named reactions,carbon–heteroatom coupling reactions,and multi-component coupling reactions have been reported and extensively applied in medicinal chemistry and materials science.The components and geometries of metal nanoclusters,such as ligands,motifs,metal cores,and supports,affect their catalytic abilities synergistically.This review summarizes carbon–carbon and carbon–heteroatom coupling reactions over atomically precise nanoclusters and highlights the correlations between nanoclusters’catalytic properties and their specific components.Guidance for choosing suitable nanoclusters for specific coupling reactions and possible research directions in this field have been proposed.We hope that this review will provide researchers attempting to study the coupling reactions catalyzed by metal nanoclusters with a comprehensively catalytic toolbox and insightful research fundamentals,so as to provide tailor-made approaches to achieve more efficient cluster-based catalysts towards coupling reactions.展开更多
The catalytic activation of the C-N bond is the most challenging and least explored amongst all cross coupling reactions because of the high dissociation energy of the C-N bond.Herein,we synthesized a new palladium-di...The catalytic activation of the C-N bond is the most challenging and least explored amongst all cross coupling reactions because of the high dissociation energy of the C-N bond.Herein,we synthesized a new palladium-di-pyrazole framework(Pd-MOF)through the strategic exchange of metal nodes in a Cu MOF with Pd(II)ions.Pd-MOF proved to be an excellent catalyst in forming a C-C bond via cleavage of the C-N bond of arylhydrazines.The catalyst was found to be size and shape-selective for the substitu ents and recyclable for at least four catalytic cycles without losing its activity.展开更多
Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_...Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_(4)N)_(2)[Pd(4-MeOpma)_(2)](4)and(n-Bu_(4)N)_(2)[Pd(4-Isopma)_(2)](5)(n-Bu_(4)N+=tetra-n-butylammonium,4-Fpma=N-4-fluorophenyloxamate,4-Clpma=N-4-chlorophenyloxamate,4-Brpma=N-4-bromophenyloxamate,4-MeOpma=N-4-methoxyphenyloxamate and 4-isopma=N-4-isopropylphenyloxamate)have been easily prepared and characterized by spectroscopic methods and the crystal structures of two of them(3a and 4)have been determined by single crystal X-ray diffraction.Each palladium(Ⅱ)ion in 3a and 4 is four-coordinate with two oxygen and two nitrogen atoms from two fully deprotonated oxamate ligands building a centrosymmetric square planar PdN_(2)O_(2)surrounding.The values of the Pd-N and Pd-O bond lengths vary in the ranges 2.034(3)-2.043(4)and 1.999(4)-2.013(3)Å,respectively.The reduced bite of the chelating oxamate ligands[81.3(2)-81.7(1)(3a)and 81.61(7)°(4)]is at the origin of the mean distortion of the ideal square environment.The catalytic role of compounds 1-5 as structurally well-defined precatalysts for the Heck-vinylation of a series of aryl iodide/bromide derivatives in n-Bu_(4)NBr as a benign nonaqueous ionic liquid(i.d.molten salt)has been examined and compared with some commercially available palladium(Ⅱ/0)complexes.From this study,it appears that the oxamate-containing precatalysts 1-5 are not just ecologically benign,but also highly efficient,easily recoverable and reusable at least eight times without any relevant loss of catalytic activity or leaching from the ionic liquid medium.展开更多
The synthesis and full characterization of several transition metal complexes of a redox-switchable,biaryl(Ar^(T))-substituted[1]phosphaferrocenophane,FcPAr^(T)(L2),in conjunction with some palladium complexes of the ...The synthesis and full characterization of several transition metal complexes of a redox-switchable,biaryl(Ar^(T))-substituted[1]phosphaferrocenophane,FcPAr^(T)(L2),in conjunction with some palladium complexes of the mesityl(Mes)-substituted derivative,FcPMes(L1),and the non-bridged diphenylferrocenyl phosphine,Ph_(2)PFc(L3),are reported.Cyclic voltammetry studies on the bimetallic complexes[Ir(κ^(1)P-L2)(cod)Cl](1),[Ir(κ^(1)P-L2)(CO)2Cl](2),[AuCl(κ^(1)P-L2)](3),[Pd(κ^(1)P-L2)(η^(3)-allyl)Cl](4),[Pd(κ^(1)P-L3)(η^(3)-allyl)Cl](5),[Pd(κ^(1)P-L3)(2-aminobiphenyl)(SO_(3)CH_(3))](6),and[Pd(κ^(1)P-L1)(2-aminobiphenyl)(SO_(3)CH_(3))](7)provided indications for a good electronic communication between the metal atoms.In order to confirm that the[1]ferrocenophane or 1-ferrocenyl unit might be able to electrochemically influence the reactivity of the coordinated transition metal,the palladium complexes 4-7 were employed as redox-switchable catalysts(RSC)in Buchwald-Hartwig cross-coupling reactions.The catalytic activity depends on the ligand and decreases in the series L3>L2>L1.In stirred solutions,the reaction rate can be influenced by addition of an oxidizing reagent.Some reactions were accelerated with in situ generated,cationic complexes as catalysts as compared to their neutral analogs;in some cases,the activity was found to be lower.Furthermore,steric effects play a predominant role,among other factors.展开更多
The formation of C–C bonds is a crucial aspect of organic synthesis.Synthesists'long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis.This...The formation of C–C bonds is a crucial aspect of organic synthesis.Synthesists'long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis.This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs)based on copper cyclic trinuclear units(Cu-CTUs).By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method,we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions,including C–H arylation and Sonogashira cross-coupling.The resulting JNM-7-Pd demonstrated remarkable stability and recyclability,maintaining its efficiency over at least three cycles without any decline in efficiency.展开更多
The Suzuki coupling reaction is a widely employed technique for the synthesis of biaryl compounds in various disciplines.This study introduces the development of a highly efficient and recyclable palladium-doped Silic...The Suzuki coupling reaction is a widely employed technique for the synthesis of biaryl compounds in various disciplines.This study introduces the development of a highly efficient and recyclable palladium-doped Silicalite-1(S-1)catalyst featuring a hierarchical structure,which enhances the efficacy of Suzuki coupling reactions.By utilizing tetra-n-butylphosphonium hydroxide as a structure-directing agent and adjusting the molar ratios of ethanol and water in the synthetic precursor,we successfully produced a range of porous S-1 catalysts.These catalysts displayed a unique architecture characterized by interconnected thin pillars or lamellae.The catalyst’s remarkable specific activity facilitated rapid Suzuki coupling reactions,completing within just three hours under environmentally benign conditions.The Suzuki reaction mechanism was discussed,which involves an oxidative addition of bromobenzene to heterogeneous Pd,followed by metal exchange with phenyl boronic acid and completed by a reductive elimination.Comprehensive substrate screening,selectivity assessments,and recycling studies were also undertaken.展开更多
The electrocatalytic C-N coupling reaction as a green synthesis approach for C-N bond synthesis via electrochemical processes with catalytic assistance.However,inefficient reactant adsorption onto the catalyst surface...The electrocatalytic C-N coupling reaction as a green synthesis approach for C-N bond synthesis via electrochemical processes with catalytic assistance.However,inefficient reactant adsorption onto the catalyst surface,competing side reactions,and the complexity and diversity of reaction pathways hinder its widespread application.Atomically dispersed catalysts(ADCs),as an emerging class of catalytic materials,possess precisely defined active sites,high catalytic activity,and enhanced selectivity,thereby enabling efficient electrocatalytic C-N coupling to address these challenges.This review discusses current reaction pathways for converting small molecules(CO_(2)as the carbon source,N_(2),NO_(2)^(-),NO_(3)^(-)as the nitrogen source)into high-value organic nitrogen compounds(urea,amides,oximes,and amino acids)utilizing ADCs.It specifically focuses on the critical steps within electrocatalytic C-N coupling facilitated by these catalysts,encompassing reactant adsorption,transformation and selective hydrogenation of C-/N-intermediates,and the C-N coupling reaction itself.Based on these key steps,design principles for ADCs are proposed.Finally,the synthesis strategies for ADCs-vacancy engineering,confinement strategies,and alloying-are examined,alongside the mechanisms by which they enhance catalytic activity and selectivity.展开更多
Electrochemical C–N coupling has generated intense research interest as a promising approach to reduce carbon and nitrogen emissions and store excess renewable electricity in valuable chemicals(e.g.,urea,amides,and a...Electrochemical C–N coupling has generated intense research interest as a promising approach to reduce carbon and nitrogen emissions and store excess renewable electricity in valuable chemicals(e.g.,urea,amides,and amines).In this review,we discuss the emerging trends in electrocatalytic C–N coupling reactions using CO_(2) and inorganic nitrogenous species(i.e.,dinitrogen(N_(2))),nitrate(NO_(2)^(-)),nitrite(NO_(3)^(-)),and ammonia(NH_(3))as raw materials.The related reaction mechanisms and potential design principles for advanced electrocatalysts are outlined.In addition,the effects of different reactors,including H-cells,membrane-based flow reactors,and membrane electrode assembly electrolyzers,on the coupling reactions are emphasized.Finally,the current challenges and future opportunities in this field are described.We aim to provide an up-to-date overview of the electrochemical C–N coupling system to advance progress toward its practical application.展开更多
Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd 2+ species with Schiff bases functionalized porous polymer. The catalyst...Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd 2+ species with Schiff bases functionalized porous polymer. The catalyst has been systemically investi-gated by a series of characterizations such as TEM, N 2 adsorption, NMR, IR, XPS, etc. TEM and N 2 isotherms show that the sample maintains the nanoporous structure after the modification and coordination. XPS results show that chemical state of palladium species in the catalyst is mainly +2. More importantly, the catalyst shows very high activities and excellent recycla-bility in a series of coupling reactions including Suzuki, Sonogashira, and Heck reactions. Hot filtration and poison of catalysts experiments have also been performed and the results indicate that soluble active species (mainly Pd(0) species) in-situ gener-ated from the catalyst under the reaction conditions are the active intermediates, which would redeposit to the supporter after the reactions.展开更多
文摘Photoelectrocatalysis(PEC)is extensively applied in diverse redox reactions.However,the traditional oxygen evolution reaction(OER)occurring at the(photo)anode is hindered by high thermodynamic demands and sluggish kinetics,resulting in excessive energy consumption and limited economic value of the O2 produced,thereby impeding the practical application of PEC reactions.To overcome these limitations,advanced anodic-cathodic coupling systems,as an emerging energy conversion technology,have garnered significant research interest.These systems substitute OER with lower potential,valuable oxidation reactions,significantly enhancing energy conversion efficiency,yielding high-value chemicals,while reducing energy consumption and environmental pollution.More importantly,by designing and optimizing photoelectrodes to generate sufficient photovoltage under illumination,meeting the thermodynamic and kinetic potential requirements of the reactions,and by tuning the voltage to match the current densities of the cathode and anode,coupling reactions can be achieved under bias-free conditions.In this review,we provide an overview of the mechanisms of PEC coupling reactions and summarize photoelectrode catalysts along with their synthesis methods.We further explore advanced catalyst modification strategies and highlight the latest development in advanced PEC coupling systems,including photocathodic CO_(2)reduction,nitrate reduction,oxygen reduction,enzyme activation,coupled with photoanodic organic oxidation,biomass oxidation,and pollutant degradation.Additionally,advanced in situ characterization techniques for elucidating reaction mechanisms are discussed.Finally,we propose the challenges in catalyst design,reaction systems,and large-scale applications,while offering future perspectives for PEC coupling system.This work underscores the tremendous potential of PEC coupling systems in energy conversion and environmental remediation,and provides valuable insights for the future design of such coupling systems.
文摘Palladium(Pd)‐based catalysts are essential to drive high‐performance Suzuki coupling reactions,which are powerful tools for the synthesis of functional organic compounds.Herein,we developed a solution‐rapid‐annealing process to stabilize nitrogen‐mesoporous carbon supported Pd single‐atom/cluster(Pd/NMC)material,which provided a catalyst with superior performance for Suzuki coupling reactions.In comparison with commercial palladium/carbon(Pd/C)catalysts,the Pd/NMC catalyst exhibited significantly boosted activity(100%selectivity and 95%yield)and excellent stability(almost no decay in activity after 10 reuse cycles)for the Suzuki coupling reactions of chlorobenzenes,together with superior yield and excellent selectivity in the fields of the board scope of the reactants.Moreover,our newly developed rapid annealing process of precursor solutions is applied as a generalized method to stabilize metal clusters(e.g.Pd,Pt,Ru),opening new possibilities in the construction of efficient highly dispersed metal atom and sub‐nanometer cluster catalysts with high performance.
基金financial support from the National Natural Science Foundation of China (No. 22101261)。
文摘Due to the increasing demand for the sustainability of modern organic chemistry, the development of green and powerful methods for C-C and C-B bond formation is highly desired. Among them, the transition-metal-free coupling reactions of gem–diborylalkanes emerge as one valuable tool for organic chemists in the last decade. The review covers selected representative examples. A comparison of these reactions with transition-metal-catalyzed reactions is provided. The recent example of α-boryl radical formation from gem–diborylalkanes is also briefly discussed.
文摘Binaphthalene-core phosphepine compounds with axial chirality belong to an important class of organocatalysts and ligands used in catalytic asymmetric synthesis.However,the number and application of these compounds have been limited due to the lack of efficient synthetic methods currently available to researchers.Herein,a simple and efficient palladium-catalyzed C—P cross-coupling reaction of enantiopure(R)-1 with a variety of aryl and heteroaryl halides is reported.The reaction provides access to a series of chiral binaphthalene-core phosphepine compounds using Pd(OAc)2/dippf as a catalyst,which allows most products to be formed in moderate to high yields(40%~92%)with excellent ee values(90%~99%ee).
基金the financial support by the Open Fund Project of Hubei Key Laboratory of Radiation Chemistry and Functional Materials (No. 2021KF07)the Research and Development Fund Project of Hubei University of Science and Technology (Nos. 2021ZX13, H2019004)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)。
文摘Polyanilines(PANIs) can be easily prepared from the available and cheap anilines via the oxidative polymerization reactions. Owing to the coordination of nitrogen in the material with metals, PANIs are widely used as the support of nano metal catalysts. In comparison with inorganic supports, the nano metals on PANIs were firmly anchored via the coordination bond so that they are not easily to lose during the reaction process. Moreover, since PANIs are versatile materials and their chemical features can be adjusted by introducing functional groups onto the monomers, the catalytic activities of the prepared catalysts are tunable. During the past decade, PANIs-supported nano metal catalysts have been widely applied in a variety of coupling reactions. This review aims to summarize the recent advances and give a perspective.
基金jointly supported by the National Key Research and Development Program of China (2019YFC1905800)the National Key Research & Development Program of China (2018YFC1903500)+4 种基金the commercial project by Beijing Zhong Dian Hua Yuan Environment Protection Technology Co., Ltd. (E01211200005)the Regional key projects of the science and technology service network program (STS program) of the Chinese Academy of Sciences (KFJ-STS-QYZD-153)the Ningbo Science and Technology Innovation Key Projects (2020Z099, 2022Z028)the Ningbo Municipal Commonweal Key Program (2019C10033)the support of Mineral Resources Analytical and Testing Center, Institute of Process Engineering, Chinese Academy of Science
文摘To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.
基金the Research Council of University of Maragheh for financially support of this workM.B.thanks the Sharif University of Technology for funding of this work
文摘The system,Pd（OAc）_2/imidazolium salts（L_2）,was found as an efficient catalyst in the Heck coupling reaction of olefins with aryl halides and Suzuki reactions of various aryl halides with aryl boronic acids under aerobic condition.This catalytic system demonstrates great tolerance to a wide range of groups on all substrates of aryl halides,alkenes and aryl boronic acids.
文摘CuI/ethylene diamine/K2CO3/dioxane is shown to be a useful system for the cross coupling reactions of various aryl iodides and bromides with aryl and alkyl alkynes. Compared to the conventional Sonogashira reactions, the new procedure is free of palladium and phosphines.
基金Project (No. 2004C21032) supported by the Key Technologies R &D Program of Zhejiang Province, China
文摘Sm/TiCl4 system could well integrate the high reactivity of samarium（Ⅱ） and high deoxygenation capacity of low valent titanium within one system. In this paper, the intermolecular and intramolecular reductive coupling reactions of ketones with esters mediated by metallic samarium （Sm） and a catalytic amount of titanium tetrachloride （TiCl4） were successfully developed. A series of substituted ketones and cyclic β-keto-esters were prepared in moderate to good yields under reflux and neutral conditions.
基金supported by the National Natural Science Foundation of China(No.20472079)
文摘Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.
基金supported by the Ministry of Science and Technology of China (No.2016YFA0200603)the National Natural Science Foundation of China (No.91421313 and No.21573207)Anhui Initiative in Quantum Information Technologies (AHY090300)
文摘The chemistry of acetaldehyde (CH3CHO) adsorbed on the anatase TiO2(001)-(1×4) surface has been investigated by temperature-programmed desorption (TPD) method. Our experimental results provide the direct evidence that the perfect lattice sites on the anatase TiO2(001)-(1×4) surface are quite inert for the reaction of CH3CHO, but the reduced defect sites on the surface are active for the thermally driven reductive carbon-carbon coupling reactions of CH3CHO to produce 2-butanone and butene. We propose that the coupling reactions of CH3CHO on the anatase TiO2(001)-(1×4) surface should undergo through the adsorption of paired CH3CHO molecules at the reduced defect sites, since the existing reduced Ti pairs provide the suitable adsorption sites.
基金the financial support of the NSFC(22371003 and 22101001)the Ministry of Education,the University Synergy Innovation Program of Anhui Province(GXXT-2020-053)+1 种基金the Scientific Research Program of Universities in Anhui Province(2022AH030009)the Research Program of Wuhu Hangfeng Techo Ltd(2024340104001629).
文摘The application of atomically precise nanocluster-based catalysts in organic synthesis has been practiced for decades.Such nanoclusters have been used as ideal catalysts as their structures are designable at the atomic level,their confined structures are conducive to mechanistic study,and most of them can be recycled during the synthesis process.The catalysis of coupling reactions using nanoclusters is an advanced methodology to build complicated carbohydrate scaffolds in one step.The history of atomically precise nanocluster-catalyzed coupling reactions is short;however,the past decade has witnessed the prosperity of this field-atomically precise nanocluster-catalyzed carbon–carbon coupling reactions including many named reactions,carbon–heteroatom coupling reactions,and multi-component coupling reactions have been reported and extensively applied in medicinal chemistry and materials science.The components and geometries of metal nanoclusters,such as ligands,motifs,metal cores,and supports,affect their catalytic abilities synergistically.This review summarizes carbon–carbon and carbon–heteroatom coupling reactions over atomically precise nanoclusters and highlights the correlations between nanoclusters’catalytic properties and their specific components.Guidance for choosing suitable nanoclusters for specific coupling reactions and possible research directions in this field have been proposed.We hope that this review will provide researchers attempting to study the coupling reactions catalyzed by metal nanoclusters with a comprehensively catalytic toolbox and insightful research fundamentals,so as to provide tailor-made approaches to achieve more efficient cluster-based catalysts towards coupling reactions.
文摘The catalytic activation of the C-N bond is the most challenging and least explored amongst all cross coupling reactions because of the high dissociation energy of the C-N bond.Herein,we synthesized a new palladium-di-pyrazole framework(Pd-MOF)through the strategic exchange of metal nodes in a Cu MOF with Pd(II)ions.Pd-MOF proved to be an excellent catalyst in forming a C-C bond via cleavage of the C-N bond of arylhydrazines.The catalyst was found to be size and shape-selective for the substitu ents and recyclable for at least four catalytic cycles without losing its activity.
基金Financial support from the Spanish Ministerio de Ciencia e Innovación(MCIIN)through Project CTQ2013-448449the Generalitat Valenciana(PROMETEOII/2014/070 and ISIC/2012/002)+4 种基金the Italian Ministero dell’Istruzione dell’Universitàe della Ricerca Scientifica(MiUR)the European Community’s Seventh Framework Program(FP72007-2013)through the MATERIA Project(PONa3_00370)is acknowledgedthe MCIIN for a predoctoral FPU grantthe European Commission,FSE(Fondo Sociale Europeo)Calabria Region for a post-doctoral fellowship.
文摘Five bis(oxamato)palladate(Ⅱ)complexes of the formulae(n-Bu_(4)N)_(2)[Pd(4-Fpma)_(2)](1),(n-Bu_(4)N)_(2)[Pd(4-Clpma)_(2)](2),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)](3),(n-Bu_(4)N)_(2)[Pd(4-Brpma)_(2)]·H_(2)O(3a),(n-Bu_(4)N)_(2)[Pd(4-MeOpma)_(2)](4)and(n-Bu_(4)N)_(2)[Pd(4-Isopma)_(2)](5)(n-Bu_(4)N+=tetra-n-butylammonium,4-Fpma=N-4-fluorophenyloxamate,4-Clpma=N-4-chlorophenyloxamate,4-Brpma=N-4-bromophenyloxamate,4-MeOpma=N-4-methoxyphenyloxamate and 4-isopma=N-4-isopropylphenyloxamate)have been easily prepared and characterized by spectroscopic methods and the crystal structures of two of them(3a and 4)have been determined by single crystal X-ray diffraction.Each palladium(Ⅱ)ion in 3a and 4 is four-coordinate with two oxygen and two nitrogen atoms from two fully deprotonated oxamate ligands building a centrosymmetric square planar PdN_(2)O_(2)surrounding.The values of the Pd-N and Pd-O bond lengths vary in the ranges 2.034(3)-2.043(4)and 1.999(4)-2.013(3)Å,respectively.The reduced bite of the chelating oxamate ligands[81.3(2)-81.7(1)(3a)and 81.61(7)°(4)]is at the origin of the mean distortion of the ideal square environment.The catalytic role of compounds 1-5 as structurally well-defined precatalysts for the Heck-vinylation of a series of aryl iodide/bromide derivatives in n-Bu_(4)NBr as a benign nonaqueous ionic liquid(i.d.molten salt)has been examined and compared with some commercially available palladium(Ⅱ/0)complexes.From this study,it appears that the oxamate-containing precatalysts 1-5 are not just ecologically benign,but also highly efficient,easily recoverable and reusable at least eight times without any relevant loss of catalytic activity or leaching from the ionic liquid medium.
基金financial support from the DFG-funded transregional collaborative research centre SFB/TRR 88“Cooperative effects in homo-and heterometallic complexes(3MET)”(project B4).
文摘The synthesis and full characterization of several transition metal complexes of a redox-switchable,biaryl(Ar^(T))-substituted[1]phosphaferrocenophane,FcPAr^(T)(L2),in conjunction with some palladium complexes of the mesityl(Mes)-substituted derivative,FcPMes(L1),and the non-bridged diphenylferrocenyl phosphine,Ph_(2)PFc(L3),are reported.Cyclic voltammetry studies on the bimetallic complexes[Ir(κ^(1)P-L2)(cod)Cl](1),[Ir(κ^(1)P-L2)(CO)2Cl](2),[AuCl(κ^(1)P-L2)](3),[Pd(κ^(1)P-L2)(η^(3)-allyl)Cl](4),[Pd(κ^(1)P-L3)(η^(3)-allyl)Cl](5),[Pd(κ^(1)P-L3)(2-aminobiphenyl)(SO_(3)CH_(3))](6),and[Pd(κ^(1)P-L1)(2-aminobiphenyl)(SO_(3)CH_(3))](7)provided indications for a good electronic communication between the metal atoms.In order to confirm that the[1]ferrocenophane or 1-ferrocenyl unit might be able to electrochemically influence the reactivity of the coordinated transition metal,the palladium complexes 4-7 were employed as redox-switchable catalysts(RSC)in Buchwald-Hartwig cross-coupling reactions.The catalytic activity depends on the ligand and decreases in the series L3>L2>L1.In stirred solutions,the reaction rate can be influenced by addition of an oxidizing reagent.Some reactions were accelerated with in situ generated,cationic complexes as catalysts as compared to their neutral analogs;in some cases,the activity was found to be lower.Furthermore,steric effects play a predominant role,among other factors.
基金the financial support from the National Funded Postdoctoral Researcher Program of China(GZC20230969)the financial support from the Guangdong Basic and Applied Basic Research Foundation(2024A1515010897)+2 种基金supported by the National Natural Science Foundation of China(22371091,22431006,22150004)the Guangdong Major Project of Basic and Applied Research(2019B030302009)the China Postdoctoral Science Foundation(2024M751120)。
文摘The formation of C–C bonds is a crucial aspect of organic synthesis.Synthesists'long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis.This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs)based on copper cyclic trinuclear units(Cu-CTUs).By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method,we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions,including C–H arylation and Sonogashira cross-coupling.The resulting JNM-7-Pd demonstrated remarkable stability and recyclability,maintaining its efficiency over at least three cycles without any decline in efficiency.
基金supported by the Research Foundation of China University of Petroleum-Beijing at Karamay(No.XQZX20220008)the National Natural Science Foundation of China(No.22308383)the National Key Research and Development Program of China(2022YFB3805602).
文摘The Suzuki coupling reaction is a widely employed technique for the synthesis of biaryl compounds in various disciplines.This study introduces the development of a highly efficient and recyclable palladium-doped Silicalite-1(S-1)catalyst featuring a hierarchical structure,which enhances the efficacy of Suzuki coupling reactions.By utilizing tetra-n-butylphosphonium hydroxide as a structure-directing agent and adjusting the molar ratios of ethanol and water in the synthetic precursor,we successfully produced a range of porous S-1 catalysts.These catalysts displayed a unique architecture characterized by interconnected thin pillars or lamellae.The catalyst’s remarkable specific activity facilitated rapid Suzuki coupling reactions,completing within just three hours under environmentally benign conditions.The Suzuki reaction mechanism was discussed,which involves an oxidative addition of bromobenzene to heterogeneous Pd,followed by metal exchange with phenyl boronic acid and completed by a reductive elimination.Comprehensive substrate screening,selectivity assessments,and recycling studies were also undertaken.
基金supported by the National Natural Science Foundation of China(No.22375019)Postdoctoral Fellowship Program of CPSF under Grant Number GZC20252673.
文摘The electrocatalytic C-N coupling reaction as a green synthesis approach for C-N bond synthesis via electrochemical processes with catalytic assistance.However,inefficient reactant adsorption onto the catalyst surface,competing side reactions,and the complexity and diversity of reaction pathways hinder its widespread application.Atomically dispersed catalysts(ADCs),as an emerging class of catalytic materials,possess precisely defined active sites,high catalytic activity,and enhanced selectivity,thereby enabling efficient electrocatalytic C-N coupling to address these challenges.This review discusses current reaction pathways for converting small molecules(CO_(2)as the carbon source,N_(2),NO_(2)^(-),NO_(3)^(-)as the nitrogen source)into high-value organic nitrogen compounds(urea,amides,oximes,and amino acids)utilizing ADCs.It specifically focuses on the critical steps within electrocatalytic C-N coupling facilitated by these catalysts,encompassing reactant adsorption,transformation and selective hydrogenation of C-/N-intermediates,and the C-N coupling reaction itself.Based on these key steps,design principles for ADCs are proposed.Finally,the synthesis strategies for ADCs-vacancy engineering,confinement strategies,and alloying-are examined,alongside the mechanisms by which they enhance catalytic activity and selectivity.
基金This work was financially supported in part by the National Key R&D Program of China(2020YFA0406103)NSFC(21725102,22122506,91961106,U1832156,22105192,22075267)+4 种基金Strategic Priority Research Program of the CAS(XDPB14)the Open Funding Project of National Key Laboratory of Human Factors Engineering(SYFD062010K)Anhui Provincial Natural Science Foundation(2008085J05)Youth Innovation Promotion Association of CAS(2019444)China Post-doctoral Science Foundation(2021M693065,2021TQ0322).
文摘Electrochemical C–N coupling has generated intense research interest as a promising approach to reduce carbon and nitrogen emissions and store excess renewable electricity in valuable chemicals(e.g.,urea,amides,and amines).In this review,we discuss the emerging trends in electrocatalytic C–N coupling reactions using CO_(2) and inorganic nitrogenous species(i.e.,dinitrogen(N_(2))),nitrate(NO_(2)^(-)),nitrite(NO_(3)^(-)),and ammonia(NH_(3))as raw materials.The related reaction mechanisms and potential design principles for advanced electrocatalysts are outlined.In addition,the effects of different reactors,including H-cells,membrane-based flow reactors,and membrane electrode assembly electrolyzers,on the coupling reactions are emphasized.Finally,the current challenges and future opportunities in this field are described.We aim to provide an up-to-date overview of the electrochemical C–N coupling system to advance progress toward its practical application.
基金supported by the National Natural Science Foundation of China (20973079 & 21003107)State Basic Research Project of China(2009CB623507)Fundamental Research Funds for the Central Universities (2010QNA3035)
文摘Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd 2+ species with Schiff bases functionalized porous polymer. The catalyst has been systemically investi-gated by a series of characterizations such as TEM, N 2 adsorption, NMR, IR, XPS, etc. TEM and N 2 isotherms show that the sample maintains the nanoporous structure after the modification and coordination. XPS results show that chemical state of palladium species in the catalyst is mainly +2. More importantly, the catalyst shows very high activities and excellent recycla-bility in a series of coupling reactions including Suzuki, Sonogashira, and Heck reactions. Hot filtration and poison of catalysts experiments have also been performed and the results indicate that soluble active species (mainly Pd(0) species) in-situ gener-ated from the catalyst under the reaction conditions are the active intermediates, which would redeposit to the supporter after the reactions.
