Inorganic-organic hybrid silica based tin complex as a novel, highly efficient and recyclable heterogeneous catalyst for the one-pot preparation of spirooxindoles in water

Multicomponent Reactions Using C,N-Binucleophilic Nature of Aminopyrazoles: Construction of Pyrazole-Fused Heterocycles

Synthesis of pyrazole-fused heterocycles has gained considerable attention in recent years due to their wide applications in medicinal chemistry. Aminopyrazoles are versatile building blocks for the synthesis of pyrazole-fused heterocycles by multicomponent reactions. Due to the presence of multiple reaction sites, they have fascinating chemical reactivity. Thus, they have been extensively used in multicomponent reactions for the construction of pyrazole-fused heterocycles. Although few review articles on the preparation and applications of aminopyrazoles are known in the literature, to date there is no dedicated review article on the construction of pyrazole-fused heterocycles exploring the reactivity of amino pyrazoles as C,N-binucleophiles in multicomponent reactions. Considering this, herein the multicomponent reactions for the construction of pyrazole-fused heterocycles exploring C,N-binucleophilic nature of amino pyrazoles have been reported.

5-Amino-pyrazoles: potent reagents in organic and medicinal synthesis

5-Amino-pyrazoles have proven to be a class of fascinating and privileged organic tools for the construction of diverse heterocyclic or fused heterocyclic scaffolds. This review presents comprehensively the applications of 5-amino-pyrazoles as versatile synthetic building blocks in the synthesis of remarkable organic molecules with an emphasis on versatile functionalities. Following a brief introduction of synthesis methods, planning strategies to construct organic compounds, particularly diverse heterocyclic scaffolds, such as poly-substituted heterocyclic compounds and fused heterocyclic compounds via 5-amino-pyrazoles, have been summarized. Fused heterocycles are classified as bicyclic, tricyclic, tetracyclic, and spiro-fused pyrazole derivatives. These outstanding compounds synthesized via wide variety of approaches include conventional reactions, one-pot multi-component reactions, cyclocondensation, cascade/tandem protocols, and coupling reactions. 5-Amino-pyrazoles represent a class of promising functional reagents, similar to the biologically active compounds, highlighted with diverse applications especially in the field of pharmaceutics and medicinal chemistry. Notably, this critical review covers the articles published from 1981 to 2018.

Efficient sonochemical green reaction of aldehyde, thiobarbituric acid and ammonium acetate using magnetically recyclable nanocatalyst in water

A facile one-pot and four-component economical synthesis of pyrido[2,3-d:6,5-d]dipyrimidines using aldehyde, 2-thiobarbituric acid and ammonium acetate in the presence of magnetically heterogeneous catalyst under ultrasonic irradiation in water is described. The present synthesis shows attractive characteristics such as; the use of magnetically recoverable and reusable catalyst, convenient one-pot operation, short reaction periods, high to excellent yields and the use of water as a green reaction medium, mild reaction conditions and is considered to be relatively environmentally benign.

A new type of SO3H-functionalized magnetic-titania as a robust magnetically-recoverable solid acid nanocatalyst for multi-component reactions

This paper highlights a novel synthetic strategy for the preparation of robust and magnetically-recoverable solid acid nanocatalysts.

Recent applications of barbituric acid in multicomponent reactions

This review aims to show representative examples of multicomponent reactions utilizing barbituric acid in the synthesis of various heterocyclic structures.

Pt NPs immobilized on core–shell magnetite microparticles: novel and highly efficient catalysts for the selective aerobic oxidation of ethanol and glycerol in water

Pt nanoparticles immobilized on PPy coated magnetite microparticles are highly efficient catalysts for the selective aerobic oxidation of ethanol and glycerol.

Functionalized multi-walled carbon nanotubes as an efficient reusable heterogeneous catalyst for green synthesis of N-substituted pyrroles in water

In this protocol, the functionalization of multi-walled carbon nanotubes (MWCNTs) was investigated and they were applied as a recyclable heterogeneous catalyst for the synthesis of N-substituted pyrroles.