Boosting Aerobic Oxidation of Alcohols via Synergistic Effect between TEMPO and a Composite Fe₃O₄/Cu-BDC/GO Nanocatalyst

Abstract

Fabrication of a nanocomposite catalyst via a novel and efficient strategy remains a challenge; Fe 3 O 4 nanoparticles anchored on graphene oxide (GO) sheet-supported metal-organic frameworks (MOFs). In this study, the physicochemical properties of the ensuing Fe 3 O 4 /Cu-BDC/GO are investigated using Fourier transform infrared spectrum, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray detector, and atomic absorption spectroscopy. The salient features of the nanocomposite such as Cu-MOF, synergistic effect with GO sheets, and magnetic separation characteristics make it an excellent ternary heterostructure for aerobic oxidation of alcohols. The proposed nanocatalyst and co-catalyst 2,2,6,6-tetramethylpiperidine-N-oxyl substantially enhance the catalytic performance for the aerobic oxidation under very mild and sustainable reaction conditions. The heterogeneity of Fe 3 O 4 /Cu-BDC/GO composite catalyst is affirmed with the added advantage that the initial activity is well maintained even after seven cycles.

Cucurbit[6]uril-Supported Fe3O4 Magnetic Nanoparticles Catalyzed Green and Sustainable Synthesis of 2-Substituted Benzimidazoles via Acceptorless Dehydrogenative Coupling

“… 49 − 52 Fe 3 O 4 MNPs have been used as the heterogeneous catalyst to facilitate various homocoupling and heterocoupling reactions. 53 − 57 Other applications of Fe 3 O 4 MNPs include A 3 -coupling reactions, 58 , 59 Paal–Knorr reaction, 60 aza-Micheal addition, 61 hydrogenation reactions, 62 oxidation reactions, 63 reduction reactions, 54 and so forth. Unsupported or uncapped Fe 3 O 4 MNPs have a tendency for agglomeration and thus inhibit catalytic properties.…”

Synergistic Catalysis by Copper Oxide/Graphene Oxide Nanocomposites: A Facile Approach to Prepare Quinazolines and Quinazoline Containing Triazole/Tetrazole Moieties under Mild Reaction Conditions

“…Moreover, the presence of various oxygen containing functional groups on GO sheets helps for the effective immobilization of various metal or metal oxide nanoparticles without aggregation and leaching. Up to now, various metal oxide nanoparticles supported on GO were utilized as a catalyst for diverse organic transformations [32–42] . These nanocomposites have shown excellent properties compared to individual counter parts due to the synergistic effect between GO support and metal oxide nanoparticles.…”

“…Up to now, various metal oxide nanoparticles supported on GO were utilized as a catalyst for diverse organic transformations. [32][33][34][35][36][37][38][39][40][41][42] These nanocomposites have shown ex-cellent properties compared to individual counter parts due to the synergistic effect between GO support and metal oxide nanoparticles. Furthermore, copper based nanomaterials have been extensively used as cost-effective and efficient catalysts for the construction of CÀ O, CÀ N, CÀ C, and CÀ S bonds in organic synthesis.…”

Dichiral [4.4.3.01,5]tridecane copper(II) cluster derived from a tripodal ligand having unsymmetrical podands and the linker: Synthesis, structure, surface grafting and catalytic aspects

“…Moreover, incorporation of the catalytic site on the surface of magnetic silica nanoparticles offers a clean, efficient and troublefree separation with maximum recovery of the catalyst from the reaction mixture by using a magnet which is supported by previous literature. [34][35][36][37] 2 | RESULTS AND DISCUSSION…”

“…In the past, some excellent reports are available on the usage of copper functionalized magnetic nanosilica for catalyzing organic reactions like asymmetric Henry reaction (by bis(oxazoline)copper(II) complex grafted magnetic mesoporous silica [ 30 ] ), synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones (by magnetic mesoporous SBA‐15 [ 31 ] ), Beckmann rearrangement in poly(ethylene glycol) (by copper(II) complex supported magnetic nanoparticles [ 32 ] ), synthesis of pyrano[2,3‐b]pyridine‐3‐carboxamide (by Schiff‐base copper(II) complex grafted magnetic material [ 33 ] ), Suzuki reaction (by copper/ppm palladium nanoparticles [ 34 ] ), aerobic oxidation of alcohols (by copper complex‐grafted magnetic graphene oxide [ 35 ] ), click reaction (magnetic copper‐pectin composite [ 36 ] ) and oxidation reactions at room temperature (chitosan‐dithiocarbamate magnetic nanocomposite). [ 37 ] Besides, grafting of chiral copper complexes on nonmagnetic mesostructured silica surfaces is also reported which includes bis(oxazoline)copper(II) complex for kinetic resolution of hydrobenzoin, enantioselective cyclopropanation Cu(II)salen complex grafted for Henry reaction and amino indanol‐based copper(II) complex for the asymmetric hetero‐Diels‐Alder reaction.…”