Abstract
Although N-heterocyclic carbenes (NHCs) are classically recognized in chemistry from coordination for their strong capacity electron donor , free NHC paradoxically constitute weak organic reducers. However, this paradigm can be challenged when carbene is added to certain electrophiles. I n this context, the NHC adduct formed turns out to be an organic super-reducer, a redox-active species particularly rich in electrons, capable of initiating from mono- and bi-electron transfer processes.
These organic electron donors combine high electron density with marked stabilization of oxidized states, opening up access to novel reactivities at particularly low reduction potentials. What's more, simple modifications to their structure enable their redox potential to be adjusted and, consequently , their reactivity to be controlled via mono- or bi-electronic transfers. The various studies carried out over the last years on these super-reducers NHC have enabled to better understand the mechanisms of electronic transfers and de de new radical strategies .
Beyond these new organic synthesis methodologies, concepts derived from NHC redox chemistry are finding emerging applications in a variety of fields, from materials chemistry to greenhouse gas mitigation, via the development of energy storage and conversion systems.
