Applications of iron and nickel immobilized on hydroxyapatite‐core‐shell γ‐Fe₂O₃ as a nanomagnetic catalyst for the chemoselective oxidation of sulfides to sulfoxides under solvent‐free conditions

Abstract

In the present study, Fe 2+ and Ni 2+ immobilized on hydroxyapatite-core-shell γ-Fe 2 O 3 (γ-Fe 2 O 3 @HAp-Fe 2+ and γ-Fe 2 O 3 @HAp-Ni 2+ ) with a high surface area has been synthesized and characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), and scanning electron microscope (SEM) techniques. Then, γ-Fe 2 O 3 @HAp-Fe 2+ and γ-Fe 2 O 3 @HAp-Ni 2+ were used as a new and magnetically recoverable nano catalyst for the selective oxidation of sulfides to sulfoxides with 33% aqueous H 2 O 2 (0.5 mL) as an oxidant at room temperature in good to excellent yields and short reaction time. Nontoxicity of reagent, mild reaction condition, inexpensive and high catalytic activity, simple experimental procedure, short period of conversion and excellent yields, and ease of recovery from the reaction mixture using an external magnet are the advantages of the present method.

Fe3O4@APTES@isatin-SO3H as heterogeneous and efficient catalyst for the synthesis of quinoxaline derivatives

“…Recently, the chemists have greatly focused on developing the eco-friendly catalysts and methods in the synthetic organic material and industrial fields [1,2].Over the last few decades, a growing research interest has been directed towards the preparation and application of highly efficient and recyclable catalysts in the modern synthetic processes [3][4][5][6].Magnetic Fe 3 O 4 nanoparticles have emerged as privileged support for immobilization of various functional groups such as phosphorous, nitrogen and organic moieties owing to the presence of high density hydroxyl groups on their surface, high surface area, high stability, facile magnetic separation, environmental benignity and high loading capacity [7][8][9][10][11][12][13][14][15][16][17][18]. Among the heterocyclic compounds, quinoxaline and derivatives are the most important compounds due to their biological and pharmacological properties which perform antifungal [19], insecticide [20], antibacterial [21], anticancer, antimalarial, anti-HIV [22] and antibiotics [23] activities.…”

Phosphomolybdic acid immobilized chitosan/Fe3O4: an efficient catalyst for the N-alkylation of anilines

“…In recent years, heterogenization of HPA catalysts, through immobilization onto the surface of modified materials has been received considerable attention [16][17][18]. Magnetic nanoparticles (MNPs) has received a lot of attention in case of the magnetization of solid phase [19][20][21]. In addition, MNpsare commonly used as potential support for the heteropoly acid catalysts because of easy separation from the reaction mixture using an external magnet and increasing the area of contact between the reactant particles [18][19][20][21][22][23][24].…”

“…Magnetic nanoparticles (MNPs) has received a lot of attention in case of the magnetization of solid phase [19][20][21]. In addition, MNpsare commonly used as potential support for the heteropoly acid catalysts because of easy separation from the reaction mixture using an external magnet and increasing the area of contact between the reactant particles [18][19][20][21][22][23][24]. Chitosan is a biodegradable and available polymer and can be modified easily to synthesize magnetic composite adsorbents [25,26].…”

Zinc(II)‐poly(urea‐formaldehyde) supported on magnetic nanoparticles: A hybrid nanocatalyst for green synthesis of spiropyrans, spiroxanthenes, and spiropyrimidines

“…[ 10 ] In addition, they can be used as catalysts in chemical processes. [ 11–21 ] As a result, ferrite spheres with hollow structures have many practical applications in the fields of catalysis, adsorbents, and gas sensors and attract much attention from researchers. [ 6 ] Cobalt ferrite can be used as magnetic support due to its moderate saturation magnetization, low cost, high chemical stability, and mechanical strength.…”