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Abstract
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In this work, first, boehmite nanoparticles were prepared by an eco
nomical and simple method using accessible materials, and func
tionalized with 3-chloropropyltrimethoxysilane (3-CPTMS). Then,
a nickel(II) unsymmetrical salen Schiff base complex, Ni(salenac
OH), where salenac-OH = [9-(2’,4’-dihydroxyphenyl)−5,8-diaza-4
methylnona-2,4,8-trienato](−2), was synthesized and immobilized
on the prepared chloro-functionalized boehmite nanoparticles. The
obtained Boehmite@Ni(salenac-OH) nanoparticles were character
ized using various techniques. The produced Boehmite@Ni(salenac
OH) nanoparticles were employed as an effective heterogeneous
nanocatalyst for the selective oxidation of sulfides to sulfoxides
using 30% H2O2 as a green oxidant under solvent-free conditions
as well as the oxidative coupling of thiols to disulfides with 30%
H2O2 inethanol at room temperature (25 °C). In these protocols, the
desired sulfoxides and disulfides were achieved with good to excel
lent yields without over-oxidation to unwanted by-products. The
use of this heterogeneous nanocatalyst in the mentioned organic
reaction achieved good results, including high efficiency, excellent
stability, easy recovery, and reusability of the catalyst for five contin
uouscycles. In addition, XRD andFT-IRtechniquesindicatedthatthe
structure of the catalyst remained intact after the recovery process.
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