Catalytic Asymmetric Synthesis of Dihydroquinazolinones from Imines and 2-Aminobenzamides

An unprecedented catalytic asymmetric synthesis of aminal-containing heterocyclic compounds has been developed from imines and tethered nitrogen/nitrogen nucleophiles. In the presence of 10 mol% of a commercially available chiral phosphoric acid, a range of aromatic, a,beta-unsaturated, and aliphatic imines react with 2-aminobenzamides to give dihydroquinazolinones in good to excellent yields and ee. The enantioselectivity is significantly affected by the imine N-substituent through non-bonding interactions with the chiral phosphoric acid and the 2-aminobenzamide.