Ultrasound‐promoted novel route to triazabenzo[b]cyclopenta[lm]fluorenes: An efficient NiFe₂O₄@SiO₂–SO₃H nanocatalyst‐assisted green synthesis

Abstract

A series of new triazabenzo[b]cyclopenta[lm]fluorene scaffolds have been synthesized from 1,2‐phenylenediamines, isothiocyanates and ninhydrin via a heterogeneous and efficient NiFe2O4@SiO2–SO3H nanoparticle‐catalysed, ultrasonic irradiation‐assisted, eco‐friendly protocol. The NiFe2O4@SiO2–SO3H nanopowder has been synthesized and thoroughly characterized by FTIR, powdered XRD, FESEM, HRTEM, EDX and N2 adsorption analysis. The most desirable agenda of our methodology is to evolve an eco‐friendly green protocol with minimum reaction time and easy reaction condition. A new and efficient catalyst, broad scope in substrate variation, very high yield percentages, use of green solvent and very short reaction time are the crucial advantages of our methodology.

Selective and green oxidation of alcohols and sulfides using mesostructured Cux/Cey mixed oxides

“…Different (mixed) metal oxides and active centers immobilized in various porous supports or magnetic nanoparticles are significant for these transformations. [ 5–13 ] Unfortunately, most of these procedures suffer from some impediments: harsh reaction conditions, long reaction times, low yields, insignificant reusability of the catalysts, using toxic and volatile solvents, and costly noble metals as the catalysts. Accordingly, it is essential to expand some green, cheap, and novel methodologies that are more effective.…”

l-Asparagine–EDTA–amide silica-coated MNPs: a highly efficient and nano-ordered multifunctional core–shell organocatalyst for green synthesis of 3,4-dihydropyrimidin-2(1H)-one compounds

“…44–48 Hence, in agreement of the green and sustainable chemistry process, development and the advancement of catalysts to promote MCRs are very important in synthetic and medicinal chemistry. 49–51…”

ZnFe2O4@SiO2‐ascorbic acid: Green, magnetic, and versatile catalyst for the synthesis of chromeno[2,3‐d] pyrimidine‐8‐amine and quinazoline derivatives

“…In the previous decade, we have witnessed a quick and remarkable growth in the use of nanomaterials as catalyst supports. [1][2][3][4] Magnetic nanoparticles (MNPs) have received much attention due to their unique advantages such as a high surface area to bulk ratios, [5] high activity, [6] low toxicity, [7] drug delivery property, [8] biomedical applications, [9][10][11][12] and thermal stability and easy separation. MNPs can be readily separated from a reaction medium using an external magnet, without the need for filtration or centrifugation.…”