Synergetic Effect of Iron-Doped Acidic Multi-Walled Carbon Nanotubes in the Synthesis of Diverse Substituted Five-Membered Heterocyclic Compounds

One-pot, three-component, iron-catalyzed synthesis of benzimidazoles via domino C-N bond formation

An efficient one-pot, three-component process for the synthesis of benzimidazole derivatives using a catalytic amount of Fe(iii) porphyrin has been developed. The reaction proceeds via domino C-N bond formation and cyclization reactions of benzo-1,2-quinone, aldehydes and ammonium acetate as a nitrogen source to selectively produce benzimidazole. A number of benzimidazole derivatives have been synthesized using this method in high yields under mild reaction conditions.

Applications of alkyl orthoesters as valuable substrates in organic transformations, focusing on reaction media

In this review we focus on applications of alkyl orthoesters as valuable and efficient substrates to perform various classes of two-component and multi-component organic reactions. The article has classified them according to two aspects, which are: (i) a focus on the reaction medium (solvent-free conditions, aqueous media, and organic solvents); and (ii) an examination of product structures. Reaction accomplishment under solvent-free conditions is an eco-friendly process with the absence of volatile toxic solvents, which puts it in line with green chemistry goals. Water is an interesting choice in organic transformations due to its inexpensiveness and safety. The authors hope their assessment will help chemists to attain new approaches for utilizing alkyl orthoesters in various organic synthetic methods. The review covers the corresponding literature up to the beginning of 2020.

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in "click" reactions

In recent years, many inorganic silica/carbon-based and magnetic materials have been selected to arrest copper ions through a widespread range of anchoring and embedding methodologies. These inorganic supported nanocatalysts have been found to be efficient, environmentally friendly, recyclable, and durable. In addition, one of the vital issues for expanding new, stable, and reusable catalysts is the discovery of unique catalysts. The basis and foundation of this review article is to consider the recently published developments (2014-2019) in the synthesis and catalytic applications of copper supported by silica nanocomposites, carbon nanocomposites, and magnetic nanocomposites for expanding the "click" chemistry.