Preparation and characterization of Fe3O4@SiO2@PMA:AS an efficient and recyclable nanocatalyst for the synthesis of 1-amidoalkyl-2-naphthols

Facile One-Pot Synthesis of Amidoalkyl Naphthols and Benzopyrans Using Magnetic Nanoparticle-Supported Acidic Ionic Liquid as a Highly Efficient and Reusable Catalyst

“…1 H and 13 C nuclear magnetic resonance (NMR) spectra were recorded on a Bruker AVANCE III spectrometer. The IR spectra wererun on a Nicolete spectrometer (KBr).…”

“…These 1-amidoalkyl-2-naphthol and tetrahydrobenzo [b]pyran derivatives are of particular value because of their promising biological and pharmacological activities [7][8][9]. The preparation of amidoalkyl naphthols has been carried out by a three-component condensation of aldehydes, 2-naphthols and amides using different catalysts such as Ba 3 (PO 4 ) 2 [10], Nano Al 2 O 3 [11], supported heteropolyacid [12,13], magnetic sulfonic or phosphoric acid [14][15][16], β-CD-BSA [17], [C 6 [18], MWCNT@Co-complex [19], sulfonated polynapthalene [20] and grapheme oxide [21] in the last five years.Despite undeniable advantages of these methods, a great part of themsuffer from one or more shortcomings such as high reaction temperature, prolonged reaction time, low yield and difficult catalyst separation and recovery. In addition, most of them are limited to only aromatic aldehydes and the reactions with aliphatic aldehydes were reported to suffer from low yields and harsh reaction conditions.…”

Fe3O4@SiO2-imid-PMAn as a Novel, Efficient and Reusable Magnetic Nanocatalyst for the Chemoselective Preparation and Deprotection of 1,1-Diacetates

“…Recently, our group has reported the catalytic potentiality of Fe 3 O 4 @SiO 2 @PMA as a nanocatalyst in the synthesis of 1-amidoalkyl-2-naphthols (Esmaeilpour et al 2014c). In this article, we report a new and efficient method for protection and deprotection of aromatic and aliphatic aldehydes at room temperature in the presence of Fe 3 O 4 @SiO 2 -imid-PMA n as an effective as well as highly chemoselective heterogeneous catalyst (Scheme 1).…”

“…The mixture was refluxed for 24 h under nitrogen atmosphere. After 24 h, the mixture was filtered by an external magnet, washed with acetonitrile and dichloromethane, and dried at 70°C for 6 h. Also, the same method was used for the synthesis of Fe 3 O 4 @SiO 2 -imid-PMA b (PMA n = nano H 3 PMo 12 O 40 , PMA b = H 3 PMo 12 O 40 ) (Esmaeilpour et al 2014c). …”

One-pot synthesis of multisubstituted imidazoles catalyzed by Dendrimer-PWAn nanoparticles under solvent-free conditions and ultrasonic irradiation

“…Although these materials are versatile compounds in their acidic form, their main disadvantages are high solubility in polar solvents and low surface area (\10 m 2 /g). Therefore, in a homogeneous reaction, the isolation of the products and the reuse of the catalyst after reaction become difficult [30][31][32][33]. Therefore, in order to overcome this problem, these materials are dispersed on supports (such as silica, acidic ionexchange resins, active carbon, etc.)…”