Selective C−C bond cleavage under mild conditions can serve as a valuable tool for organic syntheses and macromolecular degradation. However, the conventional chemical methods have largely involved the use of noble transition-metal catalysts as well as the stoichiometric and perhaps environmentally unfriendly oxidants, compromising the overall sustainable nature of C−C transformation chemistry. In this regard, electrochemical C−C bond cleavage has been identified as a sustainable and scalable strategy that employs electricity to replace byproduct-generating chemical reagents. To date, the progress made in this area has mainly relied on Kolbe electrolysis and related processes. Encouragingly, more and more examples of the cleavage of C−C bonds via other maneuvers have recently been developed. This review provides an overview on the most recent and significant developments in electrochemically oxidative selective C−C bond cleavage, with an emphasis on both synthetic outcomes and reaction mechanisms, and it showcases the innate advantages and exciting potentials of electrochemical synthesis. CONTENTS 1. Introduction 485 2. Cleavage of C−C Single Bonds 486 2.1. Kolbe Electrolysis and Related Processes 486 2.2. Cleavage of C sp 3 −C(O) Bonds 490 2.3. Cleavage of Vicinal Difunctional Compounds' C−C Bonds 492 2.4. Cleavage of C sp 2 −C Bonds 493 2.5. Cleavage of Bridged and Strained Cyclic C− C Bonds 495 2.6. Cleavage of C−C Bonds via Migration Reactions 497 3. Cleavage of CC Double Bonds 497 3.1. Oxygenation of CC to Carbonyl Compounds 497 3.2. Oxygenation of CC to Carboxyl Compounds 500 4. Conclusion and

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An efficiently stereoselective [4 + 2] cycloaddition of 3-alkylenyloxindoles and α-diazoketones through sequential visible-light photoactivation and N-heterocyclic carbene catalysis was achieved. A series of tetrahydropyrano­[2,3-b]­indoles with an all-carbon quaternary stereocenter were obtained in good yields with excellent diastereo- and enantioselectivities.

The enantioselective [3+4] annulation of 3-formylindol-2-methylmalonates with 2-bromoenals catalyzed by NHCs is described to efficiently synthesise functionalized azepino[1,2-a]indoles.

The combination of a chiral phosphate anion with a silver ion has been demonstrated as a powerful and synergistic ion pair catalyst for the aza-Mannich reaction. A series of valuable quaternary α,β-diamino acid derivatives was obtained in high yield, and with excellent diastereo- (up to 25:1 dr) and enantioselectivity (up to 99% ee). The adducts can be smoothly transformed into the corresponding protected chiral quaternary α,β-diamino acids by a one-pot hydrolysis reaction.