Chiral phosphoric acid catalyzed atroposelective and diastereoselective synthesis of 9-aryltetrahydroacridines

The first enantioselective synthesis of atropisomeric 9-aryltetrahydroacridines was achieved through the condensation of 2-aminoaryl ketones with alicyclic ketones. The combination of chiral phosphoric acid and an achiral primary amine promoter proved to be a competent catalytic system. Moreover, the amenability of 4-substituted cyclohexanones enabled simultaneous generation of axial and point chirality.