Silica supported Fe(HSO4)3 as an efficient, heterogeneous and recyclable catalyst for synthesis of β-enaminones and β-enamino esters

A series of beta-substituted enaminones were prepared through the one-pot reaction of beta-dicarbonyl compounds with various amines in the presence of silica ferric hydrogensulfate under solvent free conditions at room temperature. The reactions proceed smoothly in excellent yield, high chemoselectivity and with an easy work-up. Catalytic amount of Fe(HSO4)(3)center dot SiO2 catalyzed one-pot reaction of linear and cyclic beta-diketones and beta-keto esters with aromatic and aliphatic amines. The B3LYP/6-31G** full optimizations were carried out for enol-enamine tautomers of enaminones. (c) 2012 Elsevier B.V. All rights reserved.