Magnetite–Sulfuric Acid Magnetic Nanoparticles: Preparation and Applica­tion in Synthesis of Mono-, Bis-, and Tris-14H-Dibenzo[a,j]xanthen-14-yl­arenes under Solvent-Free Conditions

Abstract

Novel magnetite-sulfuric acid (Fe 3 O 4 ·SO 3 H) magnetic nanoparticles were prepared by the direct reaction of chlorosulfonic acid with magnetite nanoparticles, and characterized by IR spectroscopy, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy. The catalytic activity of the Fe 3 O 4 ·SO 3 H nanoparticles in the reaction of 2-naphthol with aryl mono-, di-and trialdehydes was examined, and these catalysts were shown to exhibit remarkable catalytic performance in the solvent-free synthesis of mono-, bis-, and tris-14H-dibenzo[a,j]xanthen-14-ylarenes. The catalyst retained its activity for several cycles.

Green synthesis and anticancer activity of tetrahydrodipyrazolo[3,4‐b:4′,3′‐e]pyridines catalyzed by phospho sulfonic acid

“…The solid acid catalysts occupied a wide area of organic synthesis in recent years, as they may nontoxic, stable at reaction conditions, ease of handling, higher catalytic activities, easy of recovery for further reuse at various types of organic reactions with outstanding selective yields. [48][49][50] In this context, the phosphosulfonic acid (PSA) has been found as an alternative solid heterogeneous eco-friendly acid catalyst for sulfuric acid at various organic transformations with its numerous benefits of lower cost, stability even at harsh reaction conditions, easy of recyclability due to its insolubility in most of the organic solvents, and noncorrosiveness over conventional acid catalysis. [51,52] Even though with these great significances, there is no much more research work published on its catalytic activity yet now.…”

Synthesis of heterocycles and fused heterocycles catalyzed by nanomaterials

“…The reactions were performed by the reaction of 2-naphthol with benzaldehyde derivatives (Scheme 88), terephthalaldehyde, isophthalaldehyde (Scheme 89) or trialdehydes 151a and 151b (Scheme 90), respectively, in the presence of 0.1 g MSA-MNP 2 under solventfree conditions 117. Fused [6-6-6-6-6] systems: one heteroatom 2.6.1.1.…”

Alkanedisulfamic Acid Functionalized Silica-Coated Magnetic Nanoparticles: Preparation and Catalytic Investigation in Synthesis of Mono-, Bis- and Tris[bis(4-hydroxycoumarinyl)methanes]

“…Although the reaction of 4-hydroxycoumarin with monoaldehydes has been investigated, [11][12][13][14][15][16][17][18][19] there have been no reports on reactions of 4-hydroxycoumarin with di-or trialdehydes for the synthesis of bis-and tris[bis(4-hydroxycoumarinyl)methanes], respectively. As a continuation of our research on the preparation and catalytic investigation of new acid-functionalized magnetic nanoparticles, 3,20 we synthesized new alkanedisulfamic acid magnetic nanoparticles (ADSA-MNPs) by direct reaction of chlorosulfonic acid with diaminoalkylsilicacoated magnetic nanoparticles (Scheme 1), and we used these nanoparticles as a catalyst system for the synthesis of mono-, bis-, and tris[bis(4-hydroxycoumarinyl)methanes] by condensation of 4-hydroxycoumarin with mono-, di-, or trialdehydes, respectively. To prepare the ADSA-MNPs, magnetic iron(III) oxide nanoparticles were treated with citric acid to give the corresponding charged nanoparticles (CMNPs).…”