Synthesis of ionic liquid modified Cu-doped layered double hydroxide magnetic as a novel nanocatalyst for azide-alkyne cycloaddition reactions

Abstract

In the current research, a novel nanoreactor catalyst containing copper doped hybrid structure into the layered double hydroxide and magnetite was strategically developed by hydrothermal approach followed by post-modification. The material was additionally surface functionalized with imidazole based ionic liquids in order to provide the better dispersion in the reaction medium while employed as catalyst. The as-synthesized material was physicochemically characterized in details over several analytical instruments like Transmission Electron microscopy (TEM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Vibrating Sample Magnetometer (VSM) and Fourier Transformed Infra-Red spectroscopy (FT-IR). The average dimension of the hybrid nanoreactor material was around 350 nm. Due to macro and microporous layered structure, it was having high surface area where the Cu ions, considered as active sites, were uniformly immobilized. This also facilitated the active sites as easily accessible by the reactive molecules. The ionic liquid decorated Cu doped hierarchical-functionalized LDH-magnetite nanostructure crafted a suitable environment to carry out the azide–alkyne cycloaddition (AAC) reaction. The prepared [email protected]/IMIL nanocatalyst is applied in the cycloaddition of alkyl halide, phenylacetylene and sodium azide to synthesis of several 1,2,3-triazole compounds with excellent yields in short reaction time. Due to inner magnetic core, the material was easily retrieved from the system and used five consecutive times with no appreciable loss in catalytic activity.