The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is consider...The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is considered a promising strategy for renewable biomass or biomass-derived intermediates conversion into high-value-added chemical feedstocks.In this review,we strongly emphasize the recent advances in photocatalytic valorization of lignin model compounds and biomassderived alcohols.We briefl y summarize the advances in photocatalytic cleavage of theβ-O-4 bond or C–C bond into usable chemicals in the lignin model.On the other hand,we clarify not only the hybrid system for cooperative biomass-relevant alcohols oxidation and hydrogen(H2)evolution but also the tunable accessibility to variation of the target products from the same alcohol reactant by catalyst design and optimization of reaction conditions.It is hoped that this review will inspire the rational design of photoredox catalysis-based systems toward efficient biomass-derived platform molecules valorization to obtain target-oriented valuable products.展开更多
Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric catalysis.Here,we report on the viability of visible light-driven cooperative p...Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric catalysis.Here,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the success.Additionally,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.展开更多
Due to its unique electronic properties,the difluoromethylene group(CF2)has served as a valuable unity in the design of biologically active molecules.Sinceγ-lactones display a broad range of biological properties,α,...Due to its unique electronic properties,the difluoromethylene group(CF2)has served as a valuable unity in the design of biologically active molecules.Sinceγ-lactones display a broad range of biological properties,α,α-difluoro-γ-lactones may exhibit unexpected biological activities,and thus their synthesis has received increasing attention.Traditional synthetic methods suffer from tedious multi-step processes,and very few effective methods have been reported recently.Herein,we describe the difunctionalization of alkenes with BrCF_(2)CO_(2)K under photoredox catalysis with the use of a boron-Lewis acid for the access toα,α-difluoro-γ-lactones.In this transformation,the alkene substrates and the used reagents,including BrCF_(2)CO_(2)K and the boron-Lewis acid,PhB(OH)2 or BF3·THF,are cheap and widely available.High efficiency and atom economy may make this protocol attractive.展开更多
Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regiose...Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regioselective bis-acylation of olefins by merging NHC organocatalysis and photoredox catalysis.With this protocol,a broad range of 1,4-diketones could be rapidly assembled using bench-stable feedstock materials.The robustness of this method was further evaluated by sensitivity screening,and good reproductivity was observed.Moreover,the diketone products could be readily converted into functionalized heterocycles,such as multi-substituted furan,pyrrole,and pyridazine.Mechanistic investigations shed light on the NHC and photoredox dual catalytic radical reaction mechanism.展开更多
Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides ...Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.展开更多
Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable atte...Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.展开更多
Internal alkynes are widespread skeletons in bioactive molecules and materials which are also used as important building blocks in chemical synthesis. Herein, we report a novel and efficient copper-catalyzed Sonogashi...Internal alkynes are widespread skeletons in bioactive molecules and materials which are also used as important building blocks in chemical synthesis. Herein, we report a novel and efficient copper-catalyzed Sonogashira reaction between sulfonium salts and alkynes through an anti-Markovnikov ring-opening pathway promoted by visible light. The coexistence of the nitrogen and phosphorus ligands in the system is the key to the success of this reaction. This radical type ring-opening reaction affords a new strategy for the synthesis of internal alkynes. Furthermore, this study is also an effective complement to the diverse reaction patterns of sulfonium salts.展开更多
Photoredox catalysis has changed the landscape of modern synthetic organic chemistry by prompting a dramatic increase in research activity into reactions that proceed through free radical intermediates.
The transition-metal-catalyzed cyanations of aryl halides are among the most used methods for synthesizing aryl nitriles.Despite tremendous advances,cyanating an aryl halide in a facile and benign fashion has generall...The transition-metal-catalyzed cyanations of aryl halides are among the most used methods for synthesizing aryl nitriles.Despite tremendous advances,cyanating an aryl halide in a facile and benign fashion has generally been unsuccessful.The challenge in this significant transformation is the strong affinity of cyanide for metals,which hampers oxidative addition(OD)and reductive elimination(RE)making organometallic catalysis elusive.Herein,we demonstrate for the first time that photoredox-nickel-catalyzed cyanations of aryl halides are readily enabled by visible light,in which Ni(Ⅱ)species are transiently oxidized to Ni(Ⅲ)species,thereby facilitating subsequent cyanide transfer and RE.Using this dual catalysis strategy,we cyanated aryl and alkenyl halides at room temperature in a highly benign manner(30 examples,53-93% yield)by avoiding the use of air-sensitive ligands,Ni(0)precursors,and hypertoxic cyanation reagents,while also limiting excess metal waste.Computational studies were also used to help understand the present transformation.展开更多
Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen bonds.Therefore,it is of great scientific significance to develop efficient and green methods fo...Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen bonds.Therefore,it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds,especially unsymmetrical ureas.Here,we have disclosed novel and highly efficient three-component coupling reactions of organic halides,sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical ureas.The reaction features simple and safe operations,broad substrate scopes,and product diversities.It allows the facile synthesis of N-aryl/vinyl ureas from readily available,user-friendly feedstocks under mild conditions(27 examples,36%—98%yields).In addition,this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates(15 examples,40%—95%yields).The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.展开更多
Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains chal...Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains challenging and underexplored,despite significant progress having been made in alkene difunctionalization.Here,we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO_(2),serving as a powerful bifunctional reagent for the alkylarylation of alkynes via vinyl-radical intermediate under photoredox conditions.This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups,including(hetero)aryl ring and alkyl carboxylate into alkynes,resulting in synthetically valuable all-carbon tetrasubstituted alkene derivatives.This transformation is distinguished by its redox-neutral nature,readily accessible starting materials,compatibility with diverse functional groups and its capacity to facilitate convergent synthesis.The utility of this approach was further demonstrated by the late-stage functionalization of complex molecules and the preparation of fluorescent molecules and anti-cancer drugs.展开更多
In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high effic...In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.展开更多
基金This work was supported by the National Natural Science Foundation of China(Nos.21872029,20903023,U1463204 and 21173045)the Program for Leading Talents of Fujian Universities,the Natural Science Foundation of Fujian Province for the Distinguished Young Investigator Rolling Grant(No.2017J07002)+1 种基金the 1st Program of Fujian Province for Top Creative Young Talents,the Natural Science Foundation of Fujian Province(No.2019J0106)the Award Program for Minjiang Scholar Professorship is gratefully acknowledged.
文摘The conversion of biomass into valuable chemicals has promise for application in biorefineries.Light-driven photoredox catalysis,with the typical features of green route and operation under mild conditions,is considered a promising strategy for renewable biomass or biomass-derived intermediates conversion into high-value-added chemical feedstocks.In this review,we strongly emphasize the recent advances in photocatalytic valorization of lignin model compounds and biomassderived alcohols.We briefl y summarize the advances in photocatalytic cleavage of theβ-O-4 bond or C–C bond into usable chemicals in the lignin model.On the other hand,we clarify not only the hybrid system for cooperative biomass-relevant alcohols oxidation and hydrogen(H2)evolution but also the tunable accessibility to variation of the target products from the same alcohol reactant by catalyst design and optimization of reaction conditions.It is hoped that this review will inspire the rational design of photoredox catalysis-based systems toward efficient biomass-derived platform molecules valorization to obtain target-oriented valuable products.
基金supported by the National Natural Science Foundation of China(22171072,21925103,22301061)Henan Normal University。
文摘Direct enantioselective reduction of the C=C bond ofβ-polyfluoro-alkylated enones is an important but long-pending subject in asymmetric catalysis.Here,we report on the viability of visible light-driven cooperative photoredox and chiral hydrogenbonding catalysis to effectively address this challenge,as a variety of products are obtained in high yields(up to 85%)with good to excellent enantioselectivities(up to 98%ee).The formation of thermodynamically favorable enol intermediates after double single-electron reduction represents the center of the success.Additionally,the utility of the current method is validated by the convenient regio-specific and-diverse synthesis of various deuterated derivatives for these products using inexpensive D_(2)O as the deuterium source.
基金supported by the National Key Research and Development Program of China(No.2021YFA1500703 to Ganglong Cui)Distinguished Professorship of Chang Jiang Scholars of Ministry of Education of China(Ganglong Cui)+1 种基金the Fundamental Research Funds for the Central Universitiesthe National Natural Science Foundation of China(No.22233001 to Ganglong Cui,No.22003043 to Xiang-Yang Liu)。
基金We thank the National Key Research and Development Program of China(2021YFF0701700)the National Natural Science Foundation of China(21971252,21991122,22271181)the Science and Technology Commission of Shanghai Municipality(22ZR1423600)for financial support.
文摘Due to its unique electronic properties,the difluoromethylene group(CF2)has served as a valuable unity in the design of biologically active molecules.Sinceγ-lactones display a broad range of biological properties,α,α-difluoro-γ-lactones may exhibit unexpected biological activities,and thus their synthesis has received increasing attention.Traditional synthetic methods suffer from tedious multi-step processes,and very few effective methods have been reported recently.Herein,we describe the difunctionalization of alkenes with BrCF_(2)CO_(2)K under photoredox catalysis with the use of a boron-Lewis acid for the access toα,α-difluoro-γ-lactones.In this transformation,the alkene substrates and the used reagents,including BrCF_(2)CO_(2)K and the boron-Lewis acid,PhB(OH)2 or BF3·THF,are cheap and widely available.High efficiency and atom economy may make this protocol attractive.
基金the National Natural Science Foundation of China(NSFC,Nos.22071011,21871031,22271028 and 82073998)Longquan Talents Program,the Science&Technology Department of Sichuan Province(Nos.2021YJ0404,2022JDRC0045 and 2023NSFSC1081)the innovative project of Chengdu University is gratefully acknowledged.
文摘Efficient and modular synthesis of structurally diverse 1,4-diketones from readily available building blocks represents an essential but challenging task in organic chemistry.Herein,we report a multi-component,regioselective bis-acylation of olefins by merging NHC organocatalysis and photoredox catalysis.With this protocol,a broad range of 1,4-diketones could be rapidly assembled using bench-stable feedstock materials.The robustness of this method was further evaluated by sensitivity screening,and good reproductivity was observed.Moreover,the diketone products could be readily converted into functionalized heterocycles,such as multi-substituted furan,pyrrole,and pyridazine.Mechanistic investigations shed light on the NHC and photoredox dual catalytic radical reaction mechanism.
文摘Alkyl chlorides are robust precursors to carbon radicals;however,their relative inertness has hampered their practical use.Although modern photochemical strategies have greatly enhanced the utility of alkyl chlorides as radical precursors,these methods often depend on strongly reducing conditions leading to unproductive side reactions.Here,we report a catalytic radical generation from 1°,2°,and 3°unactivated alkyl chlorides with zirconocene and photoredox catalysis,which enables both hydrogenation and borylation on a range of structurally complex molecules.This mild zirconocene-catalyzed protocol shows that zirconium can render the C−Cl bond cleavage more exergonic and can lower the activation energy of the transition state,amplifying the ability of metallocenes toward halogen atom transfer.
基金supported by the National Natural Science Foundation of China(21971110,21732003)。
文摘Transition metal catalysis is one of the most important tools to construct carbon-carbon and carbon-heteroatom bonds in modern organic synthesis. Visible-light photoredox catalysis has recently drawn considerable attention of the scientific community owing to its unique activation modes and significance for the green synthesis. The merger of photoredox catalysis with transition metal catalysts, termed metallaphotoredox catalysis, has become a popular strategy for expanding the synthetic utility of visiblelight photocatalysis. This strategy has led to the discovery of novel asymmetric transformations, which are unfeasible or not easily accessible by a single catalytic system. This contemporary area of organic chemistry holds promise for the development of economical and environmentally friendly methods for the asymmetric synthesis of chiral compounds. In this review, the advances in the enantioselective metallaphotoredox catalysis(EMPC) are summarized.
基金supported by the National Natural Science Foundation of China(22271170)the Scientific Research Foundation of Qingdao University of Science and Technology(1203043003457).
文摘Internal alkynes are widespread skeletons in bioactive molecules and materials which are also used as important building blocks in chemical synthesis. Herein, we report a novel and efficient copper-catalyzed Sonogashira reaction between sulfonium salts and alkynes through an anti-Markovnikov ring-opening pathway promoted by visible light. The coexistence of the nitrogen and phosphorus ligands in the system is the key to the success of this reaction. This radical type ring-opening reaction affords a new strategy for the synthesis of internal alkynes. Furthermore, this study is also an effective complement to the diverse reaction patterns of sulfonium salts.
文摘Photoredox catalysis has changed the landscape of modern synthetic organic chemistry by prompting a dramatic increase in research activity into reactions that proceed through free radical intermediates.
基金国家重点研发项目(2022YFA1503200,2021YFC2101901)国家自然科学基金(22122103,21971108,21971111,22271144)+1 种基金中央高校基本科研业务费(020514380304,020514380252 and 020514380272)江苏省研究生科研与实践创新计划项目(KYCX22_0100).
基金the National Science Foundation of China(nos.21822103,21820102003,21822303,21772052,21772053,and 91956201)the Program of Introducing Talents of Discipline to Universities of China(111 Program,B17019)the Natural Science Foundation of Hubei Province(no.2017AHB047).
文摘The transition-metal-catalyzed cyanations of aryl halides are among the most used methods for synthesizing aryl nitriles.Despite tremendous advances,cyanating an aryl halide in a facile and benign fashion has generally been unsuccessful.The challenge in this significant transformation is the strong affinity of cyanide for metals,which hampers oxidative addition(OD)and reductive elimination(RE)making organometallic catalysis elusive.Herein,we demonstrate for the first time that photoredox-nickel-catalyzed cyanations of aryl halides are readily enabled by visible light,in which Ni(Ⅱ)species are transiently oxidized to Ni(Ⅲ)species,thereby facilitating subsequent cyanide transfer and RE.Using this dual catalysis strategy,we cyanated aryl and alkenyl halides at room temperature in a highly benign manner(30 examples,53-93% yield)by avoiding the use of air-sensitive ligands,Ni(0)precursors,and hypertoxic cyanation reagents,while also limiting excess metal waste.Computational studies were also used to help understand the present transformation.
基金the National Natural Science Foundation of Chinaa(Nos.22271113,92256301,21822103,91956201,21820102003 and 21602052)the Natural Science Foundation of Hubei Province(No.2022CFB413)the fund from Central China Normal University for support of this research.
文摘Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen bonds.Therefore,it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds,especially unsymmetrical ureas.Here,we have disclosed novel and highly efficient three-component coupling reactions of organic halides,sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical ureas.The reaction features simple and safe operations,broad substrate scopes,and product diversities.It allows the facile synthesis of N-aryl/vinyl ureas from readily available,user-friendly feedstocks under mild conditions(27 examples,36%—98%yields).In addition,this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates(15 examples,40%—95%yields).The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.
基金supported by the National Natural Science Foundation of China(21901199)Xi’an Jiaotong University(7121192002)。
文摘Difunctionalization of alkynes represents a powerful and straightforward approach to the synthesis of complex molecules.However,the radical difunctionalization of alkynes mediated by bifunctional reagents remains challenging and underexplored,despite significant progress having been made in alkene difunctionalization.Here,we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO_(2),serving as a powerful bifunctional reagent for the alkylarylation of alkynes via vinyl-radical intermediate under photoredox conditions.This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups,including(hetero)aryl ring and alkyl carboxylate into alkynes,resulting in synthetically valuable all-carbon tetrasubstituted alkene derivatives.This transformation is distinguished by its redox-neutral nature,readily accessible starting materials,compatibility with diverse functional groups and its capacity to facilitate convergent synthesis.The utility of this approach was further demonstrated by the late-stage functionalization of complex molecules and the preparation of fluorescent molecules and anti-cancer drugs.
基金financially supported by the Young Talents Cultivation Program of the China Association for Science and Technology(No.2015-41)The Training Programme Foundation for the Talents of the Zun Yi Science and Technology Bureau(No.201540)+1 种基金Key Programs of Guizhou Province(125 Program,No.2015039)The Natural Science Foundation of Jiangsu Province(No.BK20141265)
文摘In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
