C-H Bond Functionalization under Electrochemical Flow Conditions

Abstract

Electrochemical C-H functionalization is a rapidly growing area of interest in organic synthesis. To achieve maximum atom economy, the flow electrolysis process is more sustainable. This allows shorter reaction times, safer working environments, and better selectivities. Using this technology, the problem of overoxidation can be reduced and less emergence of side products or no side products are possible. Flow electro-reactors provide high surface-to-volume ratios and contain electrodes that are closely spaced where the diffusion layers overlap to give the desired product, electrochemical processes can now be managed without the need for a deliberately added supporting electrolyte. Considering the importance of flow electrochemical C-H functionalization, a comprehensive review is presented. Herein, we summarize flow electrolysis for the construction of C-C and C-X (X=O, N, S, and I) bonds formation. Also, benzylic oxidation and access to biologically active molecules are discussed.

Keywords: C−H bonds activation; Flow electrochemistry; Green and sustainable chemistry; Microreactors; Reaction engineering.