Electrochemical Deposition of Addressable N-Heterocyclic Carbene Monolayers

Herein, we introduce an electrochemical based approach for surface-anchoring of N-heterocyclic carbene (NHC) monolayers. The deposition process is based on in-situ formation of hydroxide ions by water reduction under negative potential. The hydroxide ions function as a base for deprotonation of the imidazole cations for the formation of active carbenes that self-assemble on the electrode's surface. Therefore, the electrochemical deposition does not require dry conditions or the addition of external base for carbene activation. The high temporal and spatial proximity between the NHC's activation and surface anchoring enabled the formation of well-ordered monolayers of NHCs on Au surfaces with higher density and stability than those achieved using liquid-phase deposition.