L. Zou^#, S. Xiang^#, Y. Zhang, X. Yi, X. Zheng, J.-Q. Zhang, Y.-Q. Zou*, Q. Lu*

Radical halogenation is a fundamental and important reaction in organic synthesis. However, the short lifetimes and high reactivity of halogen radicals hinder the control over reaction selectivity. In this study, an electrophotocatalytic protocol is proposed that enables the selective haloarylation of alkenes using halogen radicals. This protocol circumvents the use of unfriendly radical initiators, toxic halogenating agents, and excessive waste generation and features a low oxidation potential (∼0.25 V vs Ag/AgCl) and effective reaction selectivity control. The robustness of the proposed method is demonstrated on a preparative scale and applied to the late-stage diversification of anti-inflammatory drugs and biologically active molecules. Anticancer treatments in cell lines have demonstrated the pharmacological activities of alkenyl halides, establishing the potential of the proposed method for drug discovery.

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P. Hu^#, W. Xu^#, L. Tian, H. Zhu, F. Li, X. Qi*, Q. Lu*

Electrochemical synthesis offers a powerful and sustainable alternative to conventional chemical manufacturing techniques. The direct and selective electrohydrogenation of olefins has enormous potential applicability; however, this reactivity has not been sufficiently demonstrated. Herein, we show that an efficient Pt-based electrocatalyst from commercially available PtCl₂ can promote such transformations. This approach enables olefins to be electrohydrogenated (often below −3.0 V vs. Ag/AgCl) at high current density (J_Geo up to 133 mA/cm²) using protons and electrons as the hydrogen source. This reaction exhibits broad functional group compatibility, requires low catalyst loading, and affords a diverse series of valuable molecules (more than 60 examples) with high chemoselectivity. In addition, highly regioselective electrocatalytic hydrogenation of olefins (r.r. > 19:1) is demonstrated using PtCl₂ and 2,2'-bipyridine.

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L. Zou, X. Zheng, X. Yi, Q. Lu* 

Enantioselective transformations of hydrocarbons to three-dimensional chiral molecules remain a significant challenge in synthetic chemistry. This study uses asymmetric paired oxidative and reductive catalysis to promote the enantioselective alkylarylation of olefins through the functionalization of C(sp³)−H bonds in alkanes. This asymmetric photoelectrocatalytic approach enables the facile construction of a wide range of enantioenriched α-aryl carbonyls with excellent enantioselectivity (up to 96% ee) from readily accessible starting materials. Notably, aryl bromides, aryl iodides, and even aryl chlorides were compatible with the developed catalytic system. Mechanistic studies reveal that alkanes and electrophiles are simultaneously activated on the electrodes.

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Y. Tao, W. Ma, R. Sun, C. Huang, Q. Lu* 

Enantioselective transformation of ubiquitous C(sp³)–H bonds into three-dimensional chiral scaffolds is of longstandinginterest to synthetic chemists. Herein, an asymmetric pairedelectrolysis enables a highly efficient and sustainable approach to theenantioselective alkylation of sulfonylimines via C(sp³)–H functionalization. In this protocol, anodic oxidation for benzylic radicalformation and Lewis acid-catalyzed sulfonylimine reduction on thecathode were seamlessly cross-coupled (up to 88% yield). Enantioenriched chiral amines containing a tetrasubstituted carbonstereocenter are accessed with high enantioselectivity (up to 96% ee). Mechanistic studies suggest that the amine generated in situ couldserve as a base to deprotonate phenols and decrease the oxidationpotential of the reaction, allowing phenols with lower potentials to bepreferentially oxidized.

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Y. Cao, C. Huang, Q. Lu* 

C. Huang^#, Y. Tao^#, X. Cao, C. Zhou, Q. Lu*

Asymmetric electrocatalysis offers exciting new strategies for the synthesis of chiral molecules through novel reaction pathways. However, simultaneous activation of reactants on both electrodes via asymmetric paired electrolysis, which is more energy efficient and economic than single half-electrode synthesis, remains a formidable challenge. Herein, an asymmetric olefin–sulfonylimine coupling via paired electrocatalysis is presented for the first time. In this protocol, Co-catalyzed hydrogen atom transfer on the anode and Ni-catalyzed sulfonylimine reduction on the cathode were seamlessly cross-coupled. The new catalytic system enables the formation of chiral amine products bearing a tetrasubstituted carbon stereocenter with a high enantioselectivity (up to 96% ee).

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L. Zou, X. Wang, S. Xiang, W. Zheng, Q. Lu* 

Due to the intrinsic inertness of alkanes, strong oxidative conditions are typically required to enable their C(sp3)−H functionalization. Herein, a paired electrocatalysis strategy was developed by integrating oxidative catalysis with reductive catalysis in one cell without interference, in which earth-abundant iron and nickel are employed as the anodic and cathodic catalysts, respectively. This approach lowers the previously high oxidation potential required for alkane activation, enabling electrochemical alkane functionalization at the ultra-low oxidation potential of ~0.25 V vs. Ag/AgCl under mild conditions. Structurally diverse alkenes, including challenging all-carbon tetrasubstituted olefins, can be accessed using readily available alkenyl electrophiles. 

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