Exploring Molecular Complexity by N-Heterocyclic Carbene Organocatalysis: New Activation and Reaction Diversity

The development of catalytic synthetic approaches towards molecular complexity from simple materials continues to be an ultimate goal in synthetic chemistry. Over the past decades, N-heterocyclic carbene (NHC) organocatalysis has been extensively investigated to provide opportunities for a vast number of novel chemical transformations. Various activation modes and reactive intermediates enabled by NHC small-molecule catalysts, such as Breslow intermediates, (homo)enolates, acyl azoliums and their derived unsaturated azoliums exhibit great potential in the construction of complicated skeletons. This personal account will summarize our group's recent work in the exploration of new activation modes of NHC catalysis towards molecular complexity with a focus on the development and applications of NHC to achieve diversity and enantioselectivity in the preparation of functional molecules.