Although the combination of electrochemistry and homogeneous catalysis has proven to be a powerful strategy for achieving a diverse array of novel transformations,some challenges such as controlling the diffusion of c...Although the combination of electrochemistry and homogeneous catalysis has proven to be a powerful strategy for achieving a diverse array of novel transformations,some challenges such as controlling the diffusion of catalyst-related species and the instability of catalysts at electrodes remain to be overcome.Herein,we review recent advances in electrochemical homogeneous catalysis,focusing on electrochemical noble-transition-metal catalysis,photoelectrochemical catalysis,and electrochemical enantioselective catalysis.The topics discussed include:(1)how the noblemetal catalystworks in the presence of cathodic hydrogen evolution,(2)how the photocatalyst gets enhanced redox property,and(3)how the enantioselectivity is regulated in a catalytic electrochemical reaction.展开更多
The merging of transition metal catalysis with electrochemistry has become a powerful tool for organic synthesis because catalysts can govern the reactivity and selectivity.However,coupling catalysts with alkyl radica...The merging of transition metal catalysis with electrochemistry has become a powerful tool for organic synthesis because catalysts can govern the reactivity and selectivity.However,coupling catalysts with alkyl radical species generated by anodic oxidation remains challenging because of electrode passivation,dimerization,and overoxidation.In this study,we developed convergent paired electrolysis for the coupling of nickel catalysts with alkyl radicals derived from photoinduced ligand-to-metal charge-transfer of cyclic alcohols and iron catalysts,providing a practical method for site-specific and remote arylation of ketones.The synergistic use of photocatalysis with convergent paired electrolysis can provide alternative avenues for metal-catalyzed radical coupling reactions.展开更多
Comprehensive Summary The radical-mediated reductive functionalization of aryl halides has been extensively studied.However,the related radical-mediated intermolecular reductive 1,2-diarylation of alkenes,using aryl h...Comprehensive Summary The radical-mediated reductive functionalization of aryl halides has been extensively studied.However,the related radical-mediated intermolecular reductive 1,2-diarylation of alkenes,using aryl halides as aryl radical sources,remains unexplored.Herein,a new electrophotocatalytic intermolecular reductive 1,2-diarylation of alkenes is reported using aryl halides and cyanoaromatics to produce polyarylated alkanes.Using synergistic cathodic reduction and visible-light photoredox catalysis,various electron-rich and electron-deficient aryl halides are combined with various alkenes and cyanoaromatics to characterize the broad substrate scope,excellent functional group compatibility,and excellent selectivity of this reaction.Mechanistic investigations reveal that this reaction may proceed via a radical process initiated by the reductive generation of aryl radicals from aryl halides and terminated by radical-radical coupling with cyanoaromatic radical anions.展开更多
Trialkylsilanes are important building blocks in organic synthesis;however,their widespread use in redox chemistry is limited by their high oxidation potentials and comparably high bond dissociation energies(BDEs)of S...Trialkylsilanes are important building blocks in organic synthesis;however,their widespread use in redox chemistry is limited by their high oxidation potentials and comparably high bond dissociation energies(BDEs)of Si-H and α-Si-C-H bonds(>92 kcal mol^(−1)).Herein,we report a new strategy for Si-H bond homolysis enabled by the synergistic combination of electrooxidation,photoinduced ligand-to-metal charge transfer(LMCT),and radical-mediated hydrogen atom transfer(HAT).Governed by the polarity-matching effect,the HAT to electrophilic MeO·or[Cl-OHCH_(3)]·from the more hydridic Si-H instead of a C-H bond allows the selective generation of silyl radicals.This electrophotocatalytic protocol provides rapid access to Si-functionalized benzimidazo-fused isoquinolinones with broad functional-group compatibility.Mechanistic studies have shown that n-Bu_(4)NCl is essential to the electrooxidation of CeCl_(3) to form the Ce(Ⅳ)species.展开更多
基金supported by the National Science Foundation of China(nos.22071105 and 22031008)the Qinglan Project of Jiangsu Education Department.
文摘Although the combination of electrochemistry and homogeneous catalysis has proven to be a powerful strategy for achieving a diverse array of novel transformations,some challenges such as controlling the diffusion of catalyst-related species and the instability of catalysts at electrodes remain to be overcome.Herein,we review recent advances in electrochemical homogeneous catalysis,focusing on electrochemical noble-transition-metal catalysis,photoelectrochemical catalysis,and electrochemical enantioselective catalysis.The topics discussed include:(1)how the noblemetal catalystworks in the presence of cathodic hydrogen evolution,(2)how the photocatalyst gets enhanced redox property,and(3)how the enantioselectivity is regulated in a catalytic electrochemical reaction.
基金supported by the National Key R&D Program of China(2021YFA1500100)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0610000)+2 种基金the National Natural Science Foundation of China(21821002,22361142834,and 22101294)the S&TCSM of Shanghai(21ZR1476500)Natural Science Foundation of Ningbo(2023J035)。
文摘The merging of transition metal catalysis with electrochemistry has become a powerful tool for organic synthesis because catalysts can govern the reactivity and selectivity.However,coupling catalysts with alkyl radical species generated by anodic oxidation remains challenging because of electrode passivation,dimerization,and overoxidation.In this study,we developed convergent paired electrolysis for the coupling of nickel catalysts with alkyl radicals derived from photoinduced ligand-to-metal charge-transfer of cyclic alcohols and iron catalysts,providing a practical method for site-specific and remote arylation of ketones.The synergistic use of photocatalysis with convergent paired electrolysis can provide alternative avenues for metal-catalyzed radical coupling reactions.
基金the National Natural Science Foundation of China(Nos.21871126 and 22271245)the Jiangxi Province Science and Technology Project(Nos.20212AEi91002 and 20224BAB213013)+1 种基金the Jiangxi Educational Committee Foundation of China(GJJ210906)the Open Research Fund of the School of Chemistry and Chemical Engineering,Henan Normal University(No.2021zD01)for theirfinancial support.
文摘Comprehensive Summary The radical-mediated reductive functionalization of aryl halides has been extensively studied.However,the related radical-mediated intermolecular reductive 1,2-diarylation of alkenes,using aryl halides as aryl radical sources,remains unexplored.Herein,a new electrophotocatalytic intermolecular reductive 1,2-diarylation of alkenes is reported using aryl halides and cyanoaromatics to produce polyarylated alkanes.Using synergistic cathodic reduction and visible-light photoredox catalysis,various electron-rich and electron-deficient aryl halides are combined with various alkenes and cyanoaromatics to characterize the broad substrate scope,excellent functional group compatibility,and excellent selectivity of this reaction.Mechanistic investigations reveal that this reaction may proceed via a radical process initiated by the reductive generation of aryl radicals from aryl halides and terminated by radical-radical coupling with cyanoaromatic radical anions.
基金supported by grants from the National Key Technology R&D Program(no.2017YFB0307502)the National Natural Science Foundation of China(no.21871019)Beijing Municipal Education Committee Project(nos.KZ202110005003 and KM202110005006).
文摘Trialkylsilanes are important building blocks in organic synthesis;however,their widespread use in redox chemistry is limited by their high oxidation potentials and comparably high bond dissociation energies(BDEs)of Si-H and α-Si-C-H bonds(>92 kcal mol^(−1)).Herein,we report a new strategy for Si-H bond homolysis enabled by the synergistic combination of electrooxidation,photoinduced ligand-to-metal charge transfer(LMCT),and radical-mediated hydrogen atom transfer(HAT).Governed by the polarity-matching effect,the HAT to electrophilic MeO·or[Cl-OHCH_(3)]·from the more hydridic Si-H instead of a C-H bond allows the selective generation of silyl radicals.This electrophotocatalytic protocol provides rapid access to Si-functionalized benzimidazo-fused isoquinolinones with broad functional-group compatibility.Mechanistic studies have shown that n-Bu_(4)NCl is essential to the electrooxidation of CeCl_(3) to form the Ce(Ⅳ)species.
