Synthesis, characterization, and molecular docking of benzodiazepines in the presence of SrFe12O19 magnetic nanocatalyst

Magnetically recoverable MFe12O19 nanoparticles as efficient and environmentally benign catalysts for gram-scale selective oxidation of olefins

Catalytic oxidation is an efficient route for synthesizing oxygenated compounds such as epoxides and aldehydes. However, developing cost-effective, environmentally friendly and selective gram-scale catalysts, in full agreement with circular economy and green chemistry principles, remains a significant challenge. Herein, we report on MFe12O19 magnetic nanoparticles (MNPs) as a novel, magnetically recoverable and selective catalyst for the oxidation of olefins. Three different MFe12O19 (M = Cu, Sn and Sr) MNPs were synthesized using the coprecipitation method and characterized by XRD, FTIR, Raman, XPS, SEM-EDX, TEM, BET, zeta potential and 57Fe Mössbauer spectroscopy. XRD analysis demonstrates that the patterns of SnFe12O19 and CuFe12O19 are totally different from those of the magnetoplumbite hexaferrite structure due to the confirmed coexistence by Rietveld refinements of SnO2-Fe2O3 and CuFe2O4-Fe2O3 as composite structures, respectively. In good agreement, Raman studies exclusively confirms the coexistence of MO x -Fe2O3 as a composite structure in MFe12O19, due to the presence of α-Fe2O3 and γ-Fe2O3 as intermediate phases during the formation process of the hexaferrite structure. Moreover, the XPS and Mössbauer results are consistent with the experimental evidence and spectroscopic characterizations. Subsequently, the catalytic activity of the as-synthesized MNPs was evaluated for the oxidation of styrene as a model olefinic substrate. Among the as-prepared MFe12O19 MNPs, the composite structure CuFe2O4-Fe2O3 in CuFe12O19 effectively enhances catalytic activity, selectivity and reusability due to the synergistic catalytic effect within a single magnetically recoverable nanostructure. Overall, MFe12O19 MNPs present a facile and greener approach using magnetically recyclable hexaferrites for selective catalytic oxidation reactions.

Immobilized nickel boride nanoparticles on magnetic functionalized multi-walled carbon nanotubes: a new nanocomposite for the efficient one-pot synthesis of 1,4-benzodiazepines

In this study, a new magnetic nanocomposite consisting of Ni2B nanoparticles anchored on magnetic functionalized multi-walled carbon nanotubes (Fe3O4/f-MWCNT/Ni2B) was synthesized and characterized using various techniques such as FT-IR, XRD, FESEM, SEM-based EDX, SEM-based elemental mapping, HRTEM, DLS, SAED, XPS, BET, TGA, and VSM. The as-prepared magnetic nanocomposite was successfully employed for the preparation of bioactive 1,4-benzodiazepines from the three-component reaction of o-phenylenediamine (1), dimedone (2), and different aldehydes (3), in polyethylene glycol 400 (PEG-400) as a solvent at 60 °C. The obtained results demonstrated that the current one-pot three-component protocol offers many advantages, such as good-to-excellent yields within acceptable reaction times, favorable TONs and TOFs, eco-friendliness of the procedure, easy preparation of the nanocomposite, mild reaction conditions, a broad range of products, excellent catalytic activity, green solvent, and reusability of the nanocomposite.

Synthetic aspects of 1,4- and 1,5-benzodiazepines using o-phenylenediamine: a study of past quinquennial

Benzodiazepines, seven-membered heterocyclic compounds having two nitrogen atoms at different positions, are ruling scaffolds in the area of pharmaceutical industry. They act as cardinal moieties in organic synthesis as well as in medicinal chemistry. Among the different benzodiazepines, 1,4- and 1,5-benzodiazepines play a far-reaching role in the field of biological activities such as anticonvulsion, anti-anxiety, sedation, and hypnotics. In the past few decades, researchers have conducted a lot of work on these moieties and developed broad, valuable, and significant approaches for their synthesis. In this review article, we recapitulate the systematic synthetic strategies of 1,4- and 1,5-benzodiazepines using o-phenylenediamine as a precursor over the past five years (2018-2022). This article will be helpful for scientists and researchers to examine and explore novel and efficient methods for the synthesis of these biologically active moieties.

Synergistic effect of GO/SrFe12O19 as magnetic hybrid nanocatalyst for regioselective ring-opening of epoxides with amines under eco-friendly conditions

Highly efficient magnetically separable hybrid GO/SrFe12O19 nanocomposite was synthesized, as catalyst for epoxide ring-opening, via dispersing M-type strontium hexaferrite (SrFe12O19) on graphene oxide (GO) sheets.

Multicomponent Synthesis and Investigations Fluorescence Activity of Chromenone-Pyrazole Compounds

A synthetic method is described to produce some chromenone-pyrazole derivatives through a one-pot multicomponent reaction using SrFe12O19 as a magnetic catalyst. This method provides quite a few merits, including the use of an effective and easy separable nanocatalyst, high yields of products, short reaction time, and easy work-up. Two of the products showed fluorescence properties, which have detected mercury ions without any interference with other ions. They can detect a tiny amount of mercury ions, which were comparable with other chemosensors. The detection limit is 4 × 10-7 and 3 × 10-8 M, respectively, for the compound I and II, respectively, which were considered very low amounts. The effect of mercury on health and environmental pollution is essential in medical science.