Fe(HSO4)3·SiO2 as an efficient, heterogeneous and recyclable catalyst for the synthesis of bis-(β-enaminones) and bis-(β-enamino esters)

Fe(HSO4)3·SiO2 is used to catalyze the condensation of β-diketones and β-keto esters with aromatic and aliphatic diamines in solvent-free conditions at room temperature. This afforded the corresponding bis-(β-enaminones) and bis-(β-enamino esters) in very good to excellent yields. Short reaction times, easy work-up procedure, and reusability of the catalyst are the merits of this study.