Supported benzimidazole‐salen Cu(II) complex: An efficient, versatile and highly reusable nanocatalyst for one‐pot synthesis of hybrid molecules

Abstract

A novel and efficient nanocatalyst consisting of benzimidazole‐salen Cu(II) complex on surface‐modified silica (BS‐Cu(II)@SiO2) was prepared. The heterogeneous nanocatalyst was characterized by FESEM, TEM, EDX, FT‐IR, XRD, ICP, and TGA. The nanocatalyst was used for the one‐pot synthesis of some target hybrid molecules. An efficient four component C–H bond activation/[3 + 2] cycloaddition and condensation/cyclization/aromatization sequence toward triazole‐benzimidazole derivatives is disclosed. This methodology provides a general and rapid synthetic route to some new triazole‐benzimidazole hybrids under mild reaction conditions. In addition, the heterogeneous nanocatalyst can be easily separated from the reaction mixture and used several times without noticeable leaching or loss of its catalytic activity. We believe this interesting one‐pot reaction as well as benzimidazole‐salen Cu(II) complex pave the way to the design and synthesis of other new hybrid molecules and metal catalysts, respectively.

Phosphomolybdic acid supported on Schiff base functionalized graphene oxide nanosheets: Preparation, characterization, and first catalytic application in the multi‐component synthesis of tetrahydrobenzo[a]xanthene‐11‐ones

“…These compounds, either alone or in a metal chelated form, are widely applied as antioxidant, anticonvulsant, antihypertensive α‐blocking agent, and in cancer diagnosis . In recent years, SBs derived from aromatic (benzene) rings containing carbonyl groups such as benzil or benzil like compounds, salicyaldehyde, and benzoin are widely used in functionalization of nanomaterials . These SB functionalized nanomaterials are used for different kinds of applications in catalysis, CO 2 capture for environmental clean‐up, antibacterial agents, fabrication of polymer nanocomposites, and electromagnetic studies …”

“…[28] In recent years, SBs derived from aromatic (benzene) rings containing carbonyl groups such as benzil or benzil like compounds, salicyaldehyde, and benzoin are widely used in functionalization of nanomaterials. [18,[29][30][31][32][33] These SB functionalized nanomaterials are used for different kinds of applications in catalysis, [18,29,30] CO 2 capture for environmental clean-up, [31] antibacterial agents, [32] fabrication of polymer nanocomposites, [33] and electromagnetic studies. [34] The synthesis of xanthenes has received significant attention because of their wide range of biological and pharmaceutical properties.…”

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

“…In 2018, silica modified with a benzimidazole-salen Cu(II) complex, 11, was synthesized in several steps [26]. Initially, 5-(chloromethyl)-2-hydroxybenzaldehyde (6) was prepared by the reaction of 2-hydroxybenzaldehyde (5) and paraformaldehyde in concentrated HCl at a temperature between 5 and 10°C…”

Tyrosol Derivatives, Bearing 3,5-Disubstituted Isoxazole and 1,4-Disubstituted Triazole, as Potential Antileukemia Agents by Promoting Apoptosis

“…Over the last decades, heterocyclic compounds and their derivatives have attracted considerable attention in agrochemistry, medicinal chemistry and other emerging areas [7]. The development of novel and efficient synthesis protocols for attractive heterocyclic scaffolds has become an important goal in modern organic synthesis [8,9]. Triazole/isoxazole derivatives are a class of N-heterocyclic compounds with a broad range of biological and pharmacological activities including antibacterial and anticancer properties [10][11][12][13][14].…”