Chiral phosphoric acids are highly efficient and enantioselective of Brønsted acid organocatalysts discovered very recently. High yields and excellent enantioselectivity were achieved in asymmetric organic reactions involving imines, such as asymmetric Mannich, reductive amination, Pictet-Spengler, aza-Diels-Alder, aza-ene reactions and so on. The presence of the Lewis basic phosphoryl moiety in proximity to the Brønsted acidic proton in chiral phosphoric acids potentially allows for bifunctional catalysis, that is, simultaneous activation of both electrophilic and necleophilic reaction components. The catalyst loading could be lowered to 0.5 mol%. The applications of chiral phosphoric acids in asymmetric organocatalytic reactions are reviewed. The reaction mechanism, catalytic activity and the asymmetric induction influenced by the structure of chiral phosphoric acids and the reaction conditions are also discussed.

Key words: enantioselectivity, asymmetric organocatalysis, chiral phosphoric acid, revi