Merging New and Old Concepts: Tandem Oxidative Radical‐Polar Crossover Ritter Amidation via Multicomponent Photo‐ and Electrochemical Processes

Abstract

Nitrogen‐containing drug molecules and pharmaceuticals are ubiquitous, rendering the construction of C–N bonds a crucial target in methodology development. The Ritter reaction is a well‐established method for accessing C–N bonds by generating amide functionality through the reaction of carbocations and nitriles. Since its discovery back in 1948, the Ritter reaction has progressively advanced towards milder and more sustainable conditions for carbocation generation. In this regard, notable contributions have been made by means of single electron transfer (SET) chemistry. Nowadays, photo‐ and electrochemistry are established methods of choice for the generation of reactive radical intermediates and their subsequent oxidation via radical‐polar crossover (RPC) mechanism. We review recent examples of tandem RPC and Ritter‐type protocols, demonstrating how photo‐ and electrochemical energies have been effectively harvested to expand the precursor pool for the Ritter reaction and also reimagine the process with novel mechanisms and additives.