Pseudo five-component process for the synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives using ZnAl₂O₄ nanoparticles in aqueous media

Abstract

In the present paper, we developed a straightforward and efficient approach to synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives by a simple one pot pseudo five component reactions using ZnAl2O4 nanoparticles as catalyst under benign reaction conditions.

Recent Developments on Five-Component Reactions

“…A common method for the synthesis of 4,4′-(arylmethylene)bis(1 H -pyrazol-5-ol) derivatives is to conduct a pseudo-5CR of two equiv each of phenylhydrazines and ethyl acetoacetate with one equiv of aromatic aldehydes through a cycloaddition-Knoevenagel-Michael reaction sequence. In recent years, the synthesis of bis(1 H -pyrazol-5-ols) has been accomplished using different catalysts, such as nanocatalyst Pd(0)-guanidine@MCM-41 [ 34 ], guanidine hydrochloride [ 35 ], α -Casein [ 36 ], ZnAl 2 O 4 nanoparticle [ 37 ], La(OTf) 2 -grafted-GO (graphene oxide) [ 38 ], amino acid-based ionic liquids (AAILs) [ 39 ], and CuCr 2 O 4 nanoparticle [ 40 ]. Catalyst-free conditions have also been reported [ 41 ].…”

A three‐component process for the synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives using nanosized nickel aluminate spinel crystals as highly efficient catalysts

“…Nickel aluminate (NiAl 2 O 4 ) is a ternary oxide including an AB 2 O 4 spinel structure that is important in many application fields because of its high surface area, high mechanical resistance, and high thermal and chemical stabilities as well as catalytic features . We have used metal aluminates with a spinel structure as a particularly effective catalyst in different chemical reactions . Consequently, we have developed a favorable microwave‐assisted approach for the preparation of 2,3‐dihydroquinazolin‐4(1 H )‐ones via the condensation reaction of isatoic anhydride, aldehydes, and primary amine or ammonium acetate using NiAl 2 O 4 spinel nanocrystals as reusable and mesoporous catalysts.…”

“…[22,23] We have used metal aluminates with a spinel structure as a particularly effective catalyst in different chemical reactions. [24,25] Consequently, we have developed a favorable microwave-assisted approach for the preparation of 2,3-dihydroquinazolin-4(1H)-ones via the condensation reaction of isatoic anhydride, aldehydes, and primary amine or ammonium acetate using NiAl 2 O 4 spinel nanocrystals as reusable and mesoporous catalysts.…”

Preparation and characterization of Fe3O4@SiO2/APTPOSS core–shell composite nanomagnetics as a novel family of reusable catalysts and their application in the one‐pot synthesis of 1,3‐thiazolidin‐4‐one derivatives

“…In recent years, utilizing environmental catalysts which can be simply recycled has received significant attention . In the study reported here, in continuation of our recent researches on the synthesis of nanoparticles, we prepared a novel recyclable heterogeneous core–shell nanomagnetic Fe 3 O 4 @SiO 2 /octakis[3‐(3‐aminopropyltriethoxysilane)propyl]octasilsesquioxane, using iron oxide MNPs as the core and the organic–inorganic hybrid silica as the shell. Then, the inorganic–organic hybrid POSS MNPs were used as an efficient new heterogeneous catalyst for the one‐pot three‐component synthesis of 1,3‐thiazolidin‐4‐ones under solvent‐free conditions (Scheme ).…”