Abstract
Electrochemical organic transformations have witnessed significant progress over the
past decades owing to their idiosyncratic redox nature. Electrochemistry is globally
acknowledged for its sustainability and environmental friendliness, whilst several
well-known redox processes are available that do not generate chemical waste or toxic
by-products. Apart from this, electrochemistry has adequate potential to steer numerous
non-spontaneous reactions, such as cross-coupling, C–C bond cleavage, radical generation,
directed C–H functionalization, etc., in a straightforward manner. Beyond electrochemical
oxidation reactions, electrochemical reductive transformations have also been enriched
in the last few years. Electrochemical reduction can be facilitated by using different
strategies, for example, by using a sacrificial electrode or a sacrificial reagent,
or can be accomplished in a divided cell. In this short review, different methods
for the functionalization of C–halogen bonds, including detailed mechanistic approaches,
are discussed.
1 Introduction
2 Different Strategies for Electrochemical Reduction
3 Functionalization of Carbon–Halogen Bonds through Electrochemical Reduction
3.1 E lectroreductive Hydrodehalogenation
3.2 Electroreductive C–C Coupling of Organohalides
3.2.1 Aryl–Aryl C–C Coupling
3.2.2 Aryl–Alkenyl C–C Coupling
3.2.3 Aryl–Alkyl C–C Coupling
3.2.4 Alkyl–Alkenyl C–C Coupling
3.2.5 Alkyl–Alkyl C–C Coupling
3.3 Electroreductive Coupling of Organohalides with Carbonyls (C=O)
3.4 Electroreductive Coupling of Organohalides with Organoboranes
4 Conclusion
Key words
electrochemistry - reduction - organohalide - redox - C–C coupling
