HClO4–SiO2 catalyzed stereoselective synthesis of β-amino ketones via a direct Mannich-type reaction

The HClO4–SiO2 catalyzed three-component, one-pot Mannich reaction of ketones, aromatic aldehydes and aromatic amines is carried out in ethanol to afford the corresponding β-amino ketones in good yields and high stereoselectivities in favor of the anti-isomer. Three new compounds are reported.