Review of electrochemical transition‐metal‐catalyzed C−H functionalization reactions

Abstract

The combination of organometallic C−H activation and electro‐catalysis has emerged as a potent synthetic technique for various molecular scaffolds since it avoids the use of harmful and expensive chemical oxidants in stoichiometric amounts. Moreover, the pre‐functionalization of substrates is not required and newer ways to perform metal‐catalyzed C−H activation reactions are possible. Here, we have discussed eletrochemically driven C−H acyloxylation, acetoxylation, oxygenation, acylation, amination, alkylation, halogenation, olefinations and C−H/N−H annulation reactions using various transition‐metal‐catalyst such as Ru, Rh, Pd, Co, Ni, Ir, Cu, Mn and Au by anodic oxidation, followed by reductive elimination to form the corresponding C−O, C−C, C−N and C−X (X=Cl, Br, S etc.) bonds. This review covers recent developments in transition‐metal‐catalyzed electrochemical C−H activation from 2007 until 2022.

Design, Synthesis, Antimicrobial Evaluation of Novel 2‐Oxo‐4‐Substituted Aryl‐Azetidine Benzotriazole Derivatives**

“…Prediction of pharmacokinetic properties [36] A computer analysis was carried out to prepare the ADME characteristics of the synthesized compound. It has been validated that the topological polar surface area (TPSA), or surface containing polar atoms, correlates using passive molecule via membranes.…”

Electrochemical Ruthenium‐Catalysed Directed C−H Functionalization of Arenes with Boron Reagents

“…The merging of electrochemistry with transition‐metal catalysis for C−H functionalization has made substantial progress in recent years for myriad transformations [47–50] . Key benefits include the avoidance of stoichiometric metal salt oxidants, instead using electricity as a “green oxidant” (Scheme 2), and access to milder reaction conditions which are more tolerant of sensitive substrates and coupling partners.…”

“…The merging of electrochemistry with transitionmetal catalysis for CÀ H functionalization has made substantial progress in recent years for myriad transformations. [47][48][49][50] Key benefits include the avoidance of stoichiometric metal salt oxidants, instead using electricity as a "green oxidant" (Scheme 2), and access to milder reaction conditions which are more tolerant of sensitive substrates and coupling partners. Previous work by Chang and co-workers has shown that post-transmetalation intermediates of cyclometalated Ir, Rh, and Ru complexes can be prepared and isolated from respective aryl-and methylboronic coupling partners at mild temperature, which will undergo oxidatively induced reductive elimination to form a CÀ C bond once subjected to chemical or electrochemical oxidation.…”

Theoretical Study on the Rhodium-Catalyzed Electrochemical C–H Phosphorylation: Insights into the Effect of Electro-oxidation on the Reaction Mechanism

“…Recently, organic electrochemistry has attracted increasing attention due to its economical and environmentally benign reaction conditions, which involve the use of electricity instead of adding sacrificial oxidants or reductants to achieve target transformation. − Hitherto, the combination of electrochemistry and transition-metal catalysis has evolved into an appealing protocol in exploring oxidative C–H bond functionalization for achieving challenging transformations. − The pivotal electro-oxidation processes are presumed to oxidize the organometallic precursors to a higher oxidation state, allowing a more readily bond-forming reductive elimination. − Notably, a series of conversions regarding the electro-oxidation-driven Rh-catalyzed C–H functionalization have been successfully realized. − …”