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Herein, a direct, metal‐free, and site‐selective electrochemical C−H carboxylation of arenes by reductive activation using CO2 as the economic and abundant carboxylic source was reported. The electrocarboxylation was carried out in an operationally simple manner with high chemo‐ and regioselectivity, setting the stage for the challenging site‐selective C−H carboxylation of unactivated (hetero)arenes. The robust nature of the electrochemical strategy was reflected by a broad scope of substrates with excellent atom economy and unique selectivity. Notably, the direct and selective C−H carboxylation of various challenging arenes worked well in this approach, including electron‐deficient naphthalenes, pyridines, simple phenyl derivatives, and substituted quinolines. The method benefits from being externally catalyst‐free, metal‐free and base‐free, which makes it extremely attractive for potential applications. [ABSTRACT FROM AUTHOR]

Herein, an efficient and facile approach to valuable β‐hydroxy acid derivatives from readily available aryl epoxides and CO2 with high chemo‐ and regioselectivity under mild and sustainable electrochemical conditions is described. This approach showed broad substrate scope and good functional‐group compatibility. In addition to aryl epoxides, four‐ to six‐membered aryl cyclic ethers could all be tolerated in the reaction to provide synthetically useful hydroxy acids with high efficiency. Further late‐stage carboxylation of complex molecules and drug derivatives demonstrated its potential application in the pharmaceutical industry. Mechanistic studies disclosed possible reaction pathways. [ABSTRACT FROM AUTHOR]

Described here is a direct catalytic asymmetric functionalization of unactivated alkyl indoles using organocatalysis. In the presence of an effective chiral urea catalyst and a phosphoric acid additive, the intermolecular C−C bond formation between alkyl indoles and trifluoropyruvates proceeded with high efficiency and enantiocontrol. Unlike previous asymmetric C(sp3−H) functionalizations of α‐azaarenes, this process does not require the use of either a strong base or an electron‐deficient substrate. The excellent enantiocontrol is particularly noteworthy in view of the severe background reaction as well as the complete inability of other types of catalysts evaluated. Control experiments, kinetic studies, and DFT calculations provided important insights into the mechanism. [ABSTRACT FROM AUTHOR]

A direct metal-free, base-free, and site-selective electrochemical C-H carboxylation of arenes by reductive activation using CO SB 2 sb as an economic and abundant carboxyl source was developed. C-H Carboxylation, CO2 Valorization, Carbon Dioxide, Electroreduction, Selectivity Keywords: C-H Carboxylation; CO2 Valorization; Carbon Dioxide; Electroreduction; Selectivity EN C-H Carboxylation CO2 Valorization Carbon Dioxide Electroreduction Selectivity 1 1 1 01/11/23 20230116 NES 230116 B A site-selective electrochemical b C-H carboxylation of arenes with CO SB 2 sb is reported by Youai Qiu and co-workers in their Research Article (e202214710). [Extracted from the article]

Herein, a direct, metal‐free, and site‐selective electrochemical C−H carboxylation of arenes by reductive activation using CO2 as the economic and abundant carboxylic source was reported. The electrocarboxylation was carried out in an operationally simple manner with high chemo‐ and regioselectivity, setting the stage for the challenging site‐selective C−H carboxylation of unactivated (hetero)arenes. The robust nature of the electrochemical strategy was reflected by a broad scope of substrates with excellent atom economy and unique selectivity. Notably, the direct and selective C−H carboxylation of various challenging arenes worked well in this approach, including electron‐deficient naphthalenes, pyridines, simple phenyl derivatives, and substituted quinolines. The method benefits from being externally catalyst‐free, metal‐free and base‐free, which makes it extremely attractive for potential applications. [ABSTRACT FROM AUTHOR]