Preparation of polydopamine sulfamic acid-functionalized magnetic Fe₃O₄nanoparticles with a core/shell nanostructure as heterogeneous and recyclable nanocatalysts for the acetylation of alcohols, phenols, amines and thiols under solvent-free conditions

Abstract

The loading of sulfonic acid groups on the surface of PDA-encapsulated Fe3O4 nanoparticles is proposed to fabricate a core–shell Fe3O4@PDA-SO3H nanocatalyst.

Cu(I)‐anchored polyvinyl alcohol coated‐magnetic nanoparticles as heterogeneous nanocatalyst in Ullmann‐type C–N coupling reactions

“…[36] In Figure 1b, the PVA-coated Fe 3 O 4 NPs can be seen. The adsorption peaks at 585 and 629 cm −1 correspond to those of Fe-O and bands at 1589 and 3419 cm −1 were associated with the surface-adsorbed water and hydroxyl groups, [30] which confirmed the presence of MNPs. Moreover, the representative peaks of [52] Furthermore, the intensity of bands at 3392 cm −1 was reduced as a result of bonding interactions between the functional groups of the composites and copper ions (Figure 1c).…”

“…The catalyst was synthesized according to the stages mentioned in Scheme 1. Initially, the prepared magnetic Fe 3 O 4 NPs, based on the chemical co-precipitation technique, [30] were coated with PVA to obtain Fe 3 O 4 @PVA magnetic nanocomposite. Afterward, the Fe 3 O 4 @PVA NPs were reacted with CuCl in water to obtain Fe 3 O 4 @PVA/CuCl.…”

“…The magnetic Fe 3 O 4 NPs were prepared according to our previous work . In 100 mL deionized water, Fe 3 O 4 NPs (1 g) were dispersed by ultrasonic bath for 20 min.…”

CoFe2O4@SiO2‐PA‐CC‐Guanidine MNPs as an Efficient Catalyst for the One‐Pot, Four‐Component Synthesis of Pyrazolopyranopyrimidines

“…Multicomponent reactions have advantages such as high atom‐economy, high stereoselectivity, low time and cost and save energy . In the past decades, the use of nanoparticles as heterogeneous catalysts in the organic synthesis was increased. Activity of heterogeneous catalysts…”

Butane‐1‐sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles: A novel and heterogeneous catalyst for the one‐pot synthesis of barbituric acid and pyrano[2,3‐d] pyrimidine derivatives in aqueous media

“…In recent years the use of magnetic nanoparticles (MNPs) for the preparation of supported heterogeneous catalysts has attracted significant attention. [1][2][3][4][5][6][7][8][9][10][11][12] This attention can be attributed to the unique properties of these types of compounds including high thermal and mechanical stability, large surface area to volume ratio, low toxicity, ease of recovery by use of an external magnetic field and well-defined pore size distribution. [13] In this regard magnetic metal oxide nanoparticles and especially Fe 3 O 4 nanoparticles have been the focus of much research recently.…”