Catalytic Enantioselective Reactions with (Benzo)Pyrylium Salts

The use of (benzo)pyrylium salts as versatile synthetic building blocks has become an attractive platform for the preparation of valuable heterocyclic compounds. Besides other numerous direct applications of (benzo)pyryliums, the intrinsic electrophilic nature of these species or the dipole character of the related oxidopyrylium derivatives have been exploited towards the development of enantioselective transformations such as nucleophilic dearomatization and cycloaddition reactions. This review aims at providing an overview on the relevant catalytic enantioselective methodologies developed in the past years, which are presented considering the involved metal- and/or organic catalytic system, as well as the type of reaction