Electrochemistry in organics: a powerful tool for “green” synthesis

Advances in electro-organic synthesis are associated with searching for new innovative synthetic approaches, especially those to synthesizing and functionalizing complex molecules for medicinal chemistry through functionalization and diversification at later stages, as well as with the desire to minimize waste and ensure energy efficient chemical transformations for future industrial processes. Organic chemistry is a branch of science possessing almost infinite possibilities of performing chemical reactions, identifying the mechanisms of complex processes, and generating active reagents, such as radicals, radical ions, and metals in various oxidation states, including unusual ones. In many cases, reasonably choosing an electrode potential and excluding any external oxidants or reductants allow controlling the process selectivity. In many cases, very large range of applicable electrode potentials makes electrochemistry capable of both oxidizing/reducing low-reactive molecules and fine-tuning the chemoselectivity of functional group conversions. Using mediators or catalysts, the active forms of which are generated on the electrodes and then react with the desired compounds within the solution volume, makes it possible to reduce the potential of electrolyses and increase the rates of processes. Currently, some new areas can be discerned in the organic electrosynthesis research, including the integration with well-developed and emerging process techniques, such as flow chemistry for scaling-up processes to increase efficiency and sustainability. In this review, some examples of synthetic organic electrochemistry are considered, which are based on the principles of green chemistry. They are of interest, in terms of developing and teaching the methodology of organic synthesis and electrosynthesis.