Heterogenized Cu (II) salen complex grafted on graphene oxide nanosheets as a precursing catalyst for the Pd‐free Sonogashira coupling

Abstract

Funding informationUniversity of Birjand Cu (II) salen complex immobilized on graphene oxide nanosheets [Cu (II) salen@GO] was synthesized with 3-chloropropyltrimethoxysilan as a linker and wholly characterized using various techniques like X-ray diffraction, Fourier-transform infrared, scanning electron microscopy/energy-dispersive X-ray spectroscopy, transmission electron microscopy, as well as atomic absorption spectroscopy (AAS). Cu (II) salen@GO as an effective heterogeneous catalyst has been investigated for the Sonogashira coupling reaction in dimethylsulfoxide with good to high yield (98%) in 4 hr at 110°C when the loading of Cu was 0.7 mmol g −1 based on Cu element analysis by AAS. It was understood that heterogeneous catalyst was as active as its homogeneous analog, and presented good recoverability and no significant loss in activity within successive runs.

An asymmetric Salamo-based Zn complex supported on Fe3O4 MNPs: a novel heterogeneous nanocatalyst for the silyl protection and deprotection of alcohols under mild conditions

“…[41][42][43][44][45][46][47][48][49][50][51][52] The ease of isolation and separation of the heterogeneous catalysts from the desired organic product and the recyclability and reusability further enhanced the sustainability of the catalysts. [53][54][55][56][57][58][59][60] Moreover, the heterogeneous catalysts not only catalyze the reactions on their own, but also serve as an effective support for the immobilization of active catalysts and facilitate the efficient magnetic separation of the catalysts for their recovery and reusability. [61][62][63] The functionalization and modication of iron oxide nanoparticles with numerous biocompatible and biodegradable materials in many different ways have been demonstrated with efficient and effective catalysts.…”

Boehmite@SiO2@ Tris (hydroxymethyl)aminomethane‐Cu(I): a novel, highly efficient and reusable nanocatalyst for the C‐C bond formation and the synthesis of 5‐substituted 1H‐tetrazoles in green media

“…[40] However, the homogenous Cu complexes suffer from significant drawbacks; including, the difficulty of separation and recovery of Cu complexes from the reaction system, high costs and the potential environmental pollution. [41][42][43] However, separation, purification, and reusability of homogeneous catalysts are tedious process. [44][45][46][47] On the other hand, easy separation and consecutive reusability of heterogeneous catalyst makes their consideration for industrial and laboratorial aims.…”

The new Schiff‐base complex of copper(II) grafted on mesoporous KIT‐6 as an effective nanostructure catalyst for the homoselective synthesis of various tetrazoles

“…The obtained product was washed with H 2 O, methanol, and EtOH, respectively, and then, it was dried for 4 hours at 70 C. The final product was purified through recrystallization. 56,57 The pure product was characterized using NMR and FT-IR spectroscopies.…”