The synergistic integration of metal catalysis with electrochemistry has emerged as a powerful tool for organic synthesis.However,in nickel-catalyzed electrochemical crosscoupling reactions,mismatches between external...The synergistic integration of metal catalysis with electrochemistry has emerged as a powerful tool for organic synthesis.However,in nickel-catalyzed electrochemical crosscoupling reactions,mismatches between external conditions and reaction rates often lead to side reactions such as catalyst deactivation,homocoupling,and protonation.Addressing this issue through the development of strategies is highly desirable.Herein,we report the successful merging of photochemistry with electrochemistry to facilitate nickel-catalyzed C−O cross-coupling reactions,providing a practical method for the synthesis of alkyl aryl ethers.Preliminary mechanistic studies suggest that this photoelectrochemical strategy effectively enhances the efficiency of nickelcatalyzed C−O cross-coupling reactions compared to traditional electrochemical methods by regenerating the active Ni^(Ⅰ) catalyst from the Ni^(Ⅱ) species through photochemistry.展开更多
Organic electrosynthesis has been widely used as an environmentally conscious alternative to conventional methods for redox reactions because it utilizes electric current as a traceless redox agent instead of chemical...Organic electrosynthesis has been widely used as an environmentally conscious alternative to conventional methods for redox reactions because it utilizes electric current as a traceless redox agent instead of chemical redox agents. Indirect electrolysis employing a redox catalyst has received tremendous attention, since it provides various advantages compared to direct electrolysis. With indirect electrolysis, overpotential of electron transfer can be avoided, which is inherently milder, thus wide functional group tolerance can be achieved. Additionally, chemoselectivity, regioselectivity, and stereoselectivity can be tuned by the redox catalysts used in indirect electrolysis. Furthermore, electrode passivation can be avoided by preventing the formation of polymer films on the electrode surface. Common redox catalysts include N-oxyl radicals, hypervalent iodine species, halides, amines, benzoquinones(such as DDQ and tetrachlorobenzoquinone), and transition metals. In recent years, great progress has been made in the field of indirect organic electrosynthesis using transition metals as redox catalysts for reaction classes including C–H functionalization, radical cyclization, and cross-coupling of aryl halides-each owing to the diverse reactivity and accessible oxidation states of transition metals. Although various reviews of organic electrosynthesis are available, there is a lack of articles that focus on recent research progress in the area of indirect electrolysis using transition metals, which is the impetus for this review.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
基金supported by National Key R&D Program of China(2021YFA1500100)NSF of China(21821002,22101294,22425111,22361142834)+2 种基金S&TCSM of Shanghai(21ZR1476500)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0610000)Natural Science Foundation of Ningbo Municipality(2023J035).
文摘The synergistic integration of metal catalysis with electrochemistry has emerged as a powerful tool for organic synthesis.However,in nickel-catalyzed electrochemical crosscoupling reactions,mismatches between external conditions and reaction rates often lead to side reactions such as catalyst deactivation,homocoupling,and protonation.Addressing this issue through the development of strategies is highly desirable.Herein,we report the successful merging of photochemistry with electrochemistry to facilitate nickel-catalyzed C−O cross-coupling reactions,providing a practical method for the synthesis of alkyl aryl ethers.Preliminary mechanistic studies suggest that this photoelectrochemical strategy effectively enhances the efficiency of nickelcatalyzed C−O cross-coupling reactions compared to traditional electrochemical methods by regenerating the active Ni^(Ⅰ) catalyst from the Ni^(Ⅱ) species through photochemistry.
基金supported by the National Natural Science Foundation of China (21821002, 21772222, and 91956112)Chinese Academy of Sciences (XDB20000000)Science and Technology Commission of Shanghai Municipality (18JC1415600 and 20JC1417100)。
文摘Organic electrosynthesis has been widely used as an environmentally conscious alternative to conventional methods for redox reactions because it utilizes electric current as a traceless redox agent instead of chemical redox agents. Indirect electrolysis employing a redox catalyst has received tremendous attention, since it provides various advantages compared to direct electrolysis. With indirect electrolysis, overpotential of electron transfer can be avoided, which is inherently milder, thus wide functional group tolerance can be achieved. Additionally, chemoselectivity, regioselectivity, and stereoselectivity can be tuned by the redox catalysts used in indirect electrolysis. Furthermore, electrode passivation can be avoided by preventing the formation of polymer films on the electrode surface. Common redox catalysts include N-oxyl radicals, hypervalent iodine species, halides, amines, benzoquinones(such as DDQ and tetrachlorobenzoquinone), and transition metals. In recent years, great progress has been made in the field of indirect organic electrosynthesis using transition metals as redox catalysts for reaction classes including C–H functionalization, radical cyclization, and cross-coupling of aryl halides-each owing to the diverse reactivity and accessible oxidation states of transition metals. Although various reviews of organic electrosynthesis are available, there is a lack of articles that focus on recent research progress in the area of indirect electrolysis using transition metals, which is the impetus for this review.
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.
