The synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives was accomplished via a three-component reaction in the presence of SO3H@imineZCMNPs as a novel, environment friendly, and reusable heterogeneous magnetic nanocatalyst under solvent-free conditions at 90 °C.
An efficient synthesis of Hantzsch 1,4-dihydropyridines via a one-pot three-component reaction
of ethyl acetoacetate, substituted aldehydes and ammonium acetate in the presence of ZnO@SnO2
mixed metal oxide nanoparticles under solvent-free conditions has been reported. Compare to the reported
reactions, this method shows attractive aspects such as cleaner reaction profile, shorter reaction
times, minimum catalyst loading and high yields. Isolated catalysts were reused for new reactions
without considerable loss of their catalytic activity.
Two efficient and direct procedures have been developed for the preparation of 1-amidoalkyl-2-naphthols by a one-pot condensation of aldehydes, 2-naphthol, and amides in the presence of trichloroacetic acid or cobalt (II) chloride as catalyst. The reactions were carried out under solvent-free media. High yields, short reaction times, easy workup of the catalyst are advantages of these procedures.
Silica gel-supported polyphosphoric acid (PPA-SiO2) was found to be highly efficient, eco-friendly and recyclable heterogeneous catalyst for the synthesis of 2,4,6-triarylpyridines through one-pot three-component reaction of acetophenone, aryl aldehydes, and ammonium acetate under solvent-free conditions. This method has several advantages, such as simple procedure with an easy work-up, short reaction times, and high yields. Furthermore, the catalyst could be recycled after a simple work-up, and used at least three times without substantial reduction in its catalytic activity.
Dihydropyrano[3,2-b]chromenedione derivatives were synthesized in moderate-to-high yields in one-pot three-component reaction from the corresponding aromatic aldehydes, kojic acid, and dimedone, in the presence of catalytic amount ofCeCl3⋅7H2O/SiO2as a nontoxic, reusable, inexpensive, and easily available reagent, under solvent-free conditions.
One-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones catalyzed by SO3H@imineZCMNPs as a novel, efficient and reusable acidic nanocatalyst under solvent-free conditions