From Imidazole toward Imidazolium Salts and N‑Heterocyclic Carbene Ligands: Electronic and Geometrical Redistribution

Investigations
dealing with N-heterocyclic carbenes and their derivatives
are usually centered on the influence that they exert by acting as
catalysts, ionic liquids, or metallodrugs and consequently on their
capabilities to tune the properties and reactivity of these systems.
In this context, we aimed to focus on the internal molecular changes
undergone by imidazole derivatives, from electronic and geometrical
points of view. This work represents an empirical evidence of the
molecular modifications that an imidazole skeleton undergoes upon
protonation, alkylation, and metalation.