Abstract
Chiral phosphoric acids derived from axially chiral biaryls and analogous chiral Bronsted acids have emerged as an attractive and widely applicable class of enantioselective organocatalysts for a variety of organic transformations. In this account article, we review our recent achievements and related works in the development of enantioselective carbon-carbon bond forming reactions using these axially chiral phosphoric acids and their analogues as chiral Bronsted acid catalysts. The contents are arranged according to the type of (pro)electrophiles, including imines, hemiaminal ethers, carbonyl compounds, and electron-rich double bonds, followed by specific reaction types. Further application to phosphoric acid/metal complex-combined catalytic systems is also highlighted.
Keywords: Bronsted acid, diels-alder reaction, enantioselectivity, ene reaction, friedel-crafts reaction, hydrogen bond, mannich reaction, organocatalysis, IMINES, Biginelli Reaction, Vinylogous Mannich Reaction, Pictet-Spengler Reaction, Aza-Ene Type Reaction, Enecarbamates, Hetero-Diels-Alder Reaction, Povarov Reaction, Two-Carbon Homologation Reaction, Aza-Petasis-Ferrier Rearrangement, Diels-Alder Reaction of Enone, Carbonyl-Ene Reaction