May 18, 2024

atena naeimi

Academic rank: Associate professor
Address: 8km of Jiroft road- Bandar Abbas, University of Jiroft P.O. Box: 364
Education: PhD. in Inorgaanic Chemistry
Phone:
Faculty:

Research

Title
Oxovanadium(IV) unsymmetrical salophen complex supported on modified silica-coated CoFe2O4 nanoparticles: A magnetically recoverable nanocatalyst for efficient and selective oxidation of sulfides and thiols
Type Article
Keywords
Magnetic nanocatalyst Oxovanadium(IV) complex Selective oxidation Sulfide Thiol
Researchers Maryam Aliavazi, Mehdi Hatefi, atena naeimi

Abstract

n this study, an oxovanadium(IV) unsymmetrical salophen complex, VO(salophen-OH) where salophen-OH = 4- [(E)-{(2-[(E)-2-hydroxybenzylidene)amino]phenyl}imino)methyl]benzene-1,3-diol, was synthesized and immo- bilized on the surface of chloro-functionalized silica-coated CoFe2O4 (CoFe2O4@SiO2@CPTMS) magnetic nanoparticles. FT-IR and EDX spectra, TEM and SEM images, XRD pattern, TGA, ICP, and VSM measurements were applied to characterize the resulting CoFe2O4@SiO2@CPTMS@VO(salophen-OH) nanoparticles. The developed CoFe2O4@SiO2@CPTMS@VO(salophen-OH) magnetic nanoparticle was used as a remarkably effi- cient nanocatalyst, which facilitates the chemo-selective oxidation of sulfides to sulfoxides using 30 % H2O2 and also enables the oxidative coupling of thiols to disulfides using urea/H2O2 (UHP) in ethanol at room temperature. This catalytic system presented disulfides and sulfoxides as optimal products that showed good to excellent yields, and there was no over-oxidation of disulfides and sulfoxides to undesirable by-products. An external magnet can be used to recover this nanocatalyst magnetically, and it can be recycled up to five times in both oxidation reactions without losing its catalytic action. Moreover, the recycled catalyst shows no major differ- ences in its XRD pattern and FT-IR spectrum compared to the fresh catalyst.