A series of novel 3,5-disubstituted isoxazoles have been synthesized, using a new, green, and versatile "one-pot three-steps" methodology. The key step is an oxidative 1,3-dipolar cycloaddition under ultrasonic irradiation, occurring in aqueous media, and mediated by cerium (IV) ammonium nitrate (CAN). CAN is a one-electron oxidant, highly soluble in water, slightly toxic and inexpensive, that allows the in situ conversion of the intermediate aldoximes into nitrile oxide. The syntheses are highly regioselective, as illustrated by the structures of the final compounds, which have been fully assessed by spectral analyses (H and C NMR, MS). This study illustrates the potency of the ultrasound activation to synthesize a set of highly functionalized heterocycles, with potential applications in biology, in short reaction times and following an eco-friendly process.
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http://dx.doi.org/10.1016/j.ultsonch.2017.07.019 | DOI Listing |
Sci Rep
January 2025
Center for Advanced Materials and Structures, School of Science and Technology, The University of Georgia, 0171, Tbilisi, Georgia.
In this work, cerium dioxide nanostructures were synthesized in an easy sonochemical way. CeO nanoparticles have received much attention in nanotechnology. CeONPs, exhibit biomimetic properties depending on their size, ratio of valency on their surface, and the ambient physico-chemical properties.
View Article and Find Full Text PDFMolecules
November 2024
National Engineering Research Center for Colloidal Materials, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
Calcium halide-based fluids are often used in drilling and completion operations due to their high density, clay inhibition and low solid content. However, there is a lack of thickeners to promote gel strength, which improves the fluid's capacity to carry and suspend cuttings. To solve this problem, the branched polymer (hereafter abbreviated as PAD-B) was prepared by the copolymerization of N,N-dimethylacrylamide (DMAM) and 2-acrylamide-2-methylpropane sulfonic acid (AMPS), using polyethylenimine as a branching agent and cerium ammonium nitrate as the initiator.
View Article and Find Full Text PDFOrg Lett
December 2024
Department of Nanopharmaceutical Sciences, and Department of Engineering, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan.
Biomacromolecules
December 2024
Macromolecular Chemistry and New Polymeric Materials, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 3, 9747AG Groningen, The Netherlands.
The biocompatibility and renewability of starch-based hydrogels have made them popular for applications across various sectors. Their tendency to incur damage after repeated use limits their effectiveness in practical applications. Improving the mechanical properties and self-healing of hydrogels simultaneously remains a challenge.
View Article and Find Full Text PDFInorg Chem
November 2024
Department of Chemistry and Center for Environmentally Beneficial Catalysis, The University of Kansas, 1567 Irving Hill Road, Lawrence, Kansas 66045, United States.
The oxidation of manganese complexes using ceric ammonium nitrate (CAN) is often complicated by the fact that cerium(IV) can serve as both an oxidant and a Lewis acid. In this work, we explore the reaction of CAN with the Mn complex [Mn(OTf)(N4py)](OTf) (N4py = ,-bis(4-methoxy-3,5-dimethyl-2-pyridylmethyl)--bis(2-pyridyl)methylamine). We chose this complex as multiple oxidation products, including oxomanganese(IV) and bis(μ-oxo)dimanganese(III,IV) complexes, have previously been reported.
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