Magnetic Fe3O4 Nanoparticles as Efficient and Reusable Catalyst for the Green Synthesis of 2-Amino-4H-chromene in Aqueous Media

Abstract

A simple and efficient protocol for one-pot three-component coupling of aldehyde, malononitrile, and resorcinol in water using magnetically recoverable Fe 3 O 4 nanoparticles at room temperature is reported. The high yields of products and short reaction time were attributed to the nanosize of about 18 nm in which the catalyst could act as a nanoreactor. This methodology is found to be fairly general and catalyst is easily separated by magnetic devices and can be reused without any apparent loss of activity for the reaction.

Modified chemical coprecipitation of magnetic magnetite nanoparticles using linear–dendritic copolymers

“…These peaks were owing to the adsorbed water on the surface of Fe 3 O 4 . The peak at 574 cm −1 corresponds to the Fe-O bond NPs (7,8).…”

“…Magnetic nanoparticles (NPs), especially magnetite (Fe 3 O 4 ), can be widely used in science, technology, and healthcare in applications such as cell separation (1), microwave absorption (2), magnetic resonance imaging (MRI) techniques (3), recording materials (3), ferrofluids (4), biological sensing (5), bioactive molecule separation (3), catalysis (6)(7)(8), and magnetic targeted therapy (9). For future highly sensitive magnetic nanostructures and biological and pharmacological applications, Fe 3 O 4 NPs with controlled size, shape, and a narrow size distribution are needed.…”

Magnetically Recyclable Nano-FDP: A Novel, Efficient Nano-Organocatalyst for the One-Pot Multi-Component Synthesis of Pyran Derivatives in Water Under Ultrasound Irradiation

“…7 shows the magnetization curve for nano-FDP. The saturation magnetization value of nano-FDP was found to be 59.89 emu/g, which is slightly lower than that of bare Fe 3 O 4 NPs (67.22 emu/g) [34] because of coating.…”

One-pot synthesis of 4-alkyl-2-amino-4H-chromene derivatives

“…There are several articles that describe the synthesis of 4-alkyl-2-amino-4H-chromene derivatives 2c,h using ultrasound irradiation and Fe 3 O 4 or MgO nanoparticles as catalyst [21][22][23][24]. However, their NMR data ( 13 C NMR data in particular) and melting points are different from ours and incorrect.…”