Recent Advances in Organocatalyst-Mediated Benzannulation Reactions

Aromatic compounds are omnipresent in organic chemistry, which are the broadest skeletons of bioactive molecules, medicines, and materials. Due to their importance, conventional methods to assemble aromatic rings have attracted considerable attention. The direct formation of benzene cores from readily available acyclic precursors offers a highly versatile and superior approach to prepare both small organic molecules and sophisticated natural products. Recently, organocatalyst-mediated annulation reaction, including phosphine-, tertiary amine-, secondary amine-, primary amine-, and NHC-mediated benzannulation reactions, is considered as an efficient method to access multi-substituted arenes. In this review, we will emphasize the selected examples of organocatalyst-mediated benzannulation reactions of available acyclic precursors for the construction of diverse aromatics.