The present work was designed based on the new multi-component reaction, which forms 2-aryl/alkyl-quinazolin-4(3H)-ones in a one-pot reaction with good to excellent yields (86–97 %) using ...2-aminobenzoic acid, organic acid, and ammonium hexafluorophosphate (NH4PF6). The advantages of the presented method include inexpensive and readily available starting materials, simple procedures, and easy workup. In this newly discovered method, ammonium hexafluorophosphate (NH4PF6) was used as a highly efficient reagent and catalyst for quinazolin-4(3H)-ones synthesis. All of the synthesized compounds were characterized by 1H NMR and 13C NMR techniques.
This study investigated the potential application of an efficient, easily recoverable, and reusable copper(II)-based catalyst bearing polyvinyl alcohol (PVA) immobilized on FeNi
3
/KCC-1/APTPOSS FeNi
...3
/KCC-1/APTPOSS/TCT/PVA/Cu(II) magnetic nano-particles (MNPs) for the
N
-formylation of amines via CO
2
hydrogenation. FeNi
3
/KCC-1/TCT/PVA/Cu(II) MNPs were thoroughly characterized by transmission electron microscopy, field emission-scanning electron microscopy, vibrating sample magnetometry, thermo-gravimetric analysis, inductively coupled plasma-mass spectrometry (ICP-MS), and the Brunauer, Emmett, and Teller method. After the reaction, only minor changes to the morphology of the catalyst recycled by the ICP-MS were evidenced, thus corroborating its robustness.
Graphical Abstract
Abstract
In the present study, corrosion inhibition performances of some pyrazolo 3,4-b quinoline-3,5-dione derivatives against the corrosion of copper metal were investigated using ...B3LYP/6-311++g(d,p) calculation level in aqueous media. Additionally, interaction energies were calculated for all the pyrazoloquinoline derivatives compounds. In the calculations it is observed that studied molecules adsorb on metal surface with the help of electron donor heteroatoms in their molecular structures. Chemical thermodynamic parameters regarding the interaction between inhibitor molecule and copper surface were estimated and discussed. Density of the electron profile analysis and chemical electrostatic potential of nuclear charges in the molecule were applied to consider the nature of a number of probable interactions between Cu metal surface and inhibitors in terms of bond critical point (BCP). Calculated quantum chemical parameters showed that the pyrazoloquinoline derivatives including the OH and NO
2
exhibit high inhibition performance.
A novel nanomagnetic catalyst has been synthesized by immobilization of triethanolamine lactate cellulose with Fe
3
O
4
NPs. The prepared catalyst has been used as an efficient and recoverable ...catalyst for the regioselective synthesis of pyrazolo quinolones by the three-component reaction of dimedone, 5-amino pyrazolone and aromatic aldehydes in ultrasound condition. This economical catalyst provides high yields of products, short experimental time and easy workup for green synthesis of pyrazolo3,4-
b
quinolone compounds. Theoretical studies have been employed to investigate the reaction mechanism by using the B3LYP/6-311G method. Electronic parameters of all components have been determined in order to reorganize the role of components in the reaction mechanism.
Graphic abstract
In the present work, a series of Ag
2
S@Ag
2
SO
4
/CSN heterostructures were synthesized by the in situ fabrication of Ag
2
S/Ag
2
SO
4
on the chitosan matrix in a straightforward method. The ...structure, morphology, and properties of the prepared heterojunctions were analyzed by different characterization methods. The photocatalytic performance of the synthesized Ag
2
S@Ag
2
SO
4
/CSN heterostructures was considered by rhodamine B (RhB) dye photodegradation. The best results were obtained when the reaction was conducted by Ag
2
S@Ag
2
SO
4
/0.1CSN with enhanced photoactivity under sunlight irradiation (99.9% degradation efficiency). In addition to the excellent photocatalytic activity, excellent recyclability and photostability under Vis and sunlight irradiation were observed in the subsequent experiment, resulting from enhanced absorption of light and decreased recombination of photogenerated electron–hole pairs in the photocatalysis process. Furthermore, the mechanism of photocatalyst reactions is described in detail by density functional theory (B3LYP/ LANL2DZ). The bandgaps of Ag
2
S and Ag
2
SO
4
were calculated 2.47 and 1.37 eV, respectively.
Graphical abstract
An unexpected regio- and stereoselective 4 + 3 cycloaddition reaction of azomethine ylides with 5-benzylidenethiazolidine-2,4-diones has been successfully developed for the synthesis of the novel ...pharmacologically active 4′,5′-dihydro-3′H-spiroindoline-3,2′-1, 3 oxazepin-2-one derivatives in basic condition. Easy purification, high yield, short experimental time and operational simplicity are specific advantages of this protocol. Furthermore, all the synthesized compounds have been evaluated for antioxidant and antibacterial activities. According to the results, most of the synthesized compounds exhibited DPPH radical scavenging activity and nine of them showed antibacterial properties. The reaction mechanism and
1
H NMR spectrum have been evaluated by B3LYP/6311G method.
Graphic abstract
We describe regioselective synthesis of pyrazolo3,4-
b
quinoline derivatives by multicomponent reaction of dimedone, 5-aminopyrazolone, and aromatic aldehydes in presence of H
3
PW
12
O
40
as ...catalyst. When this multicomponent reaction was investigated without catalyst under reflux conditions, a mixture of products was obtained, while the reaction successfully proceeded to formation of pyrazolo3,4-
b
quinoline in presence of H
3
PW
12
O
40
. Good product yield, short experimental time, and low-cost catalyst provide convenient synthesis for formation of pyrazolo3,4-
b
quinoline pharmacological compounds.
Polyaniline, polyaniline/SiO2, and poly(4-vinylpyridine) are highly effective base catalysts for the synthesis of tetrahydrobenzobpyran and 3,4-dihydropyranocchromene derivatives by the one-pot ...three-component condensation reaction of aryl aldehydes, malononitrile and α-hydroxy or α-amino activated C–H acids such as 1,3-cyclohexanedione, dimedone, 4-hydroxy-6-methylpyrone, 4-hydroxycoumarin, 1,3-dimethylbarbituric acid, and 1,3-dimethyl-6-amino uracil. The remarkable advantages of this new procedure are high yields, short experimental time, mild reaction condition, low cost and easy preparation of the catalysts, and no need for any workup and purification after completion of the reaction. In addition, these catalysts exhibited excellent recoverability without a negligible decrease of their activities after at least six cycles of reaction.
A series of biologically active disubstituted benzofuran derivatives (3a?d) have been designed and synthesized via C?H bond activation reaction. The chemical structures of all final compounds were ...confirmed by spectroscopic methods. In vitro anti acetylcholinesterase (AChE) activities of these novel compounds were evaluated and showed low to moderate results. Among them, compound 3d moderately inhibited AChE activities with 68.12 % value.
A novel magnetic photocatalyst has been synthesized by a facile hydrothermal method. In this research, the 3D urchin-like TiO2 microspheres were hydrothermally synthesized and then decorated with the ...magnetic biochar dots to prepare bare 3D-TiO2/magnetic biochar dots (3D-TiO2/BCDs MNPs). Characterization of the prepared photocatalyst was done by different analysis methods such as TEM, FE-SEM, XRD, VSM, and FT-IR. The 3D-TiO2/BCDs MNPs displayed high performance for diazinon degradation with 98.5% degradation efficiency in 30 min under sunlight irradiation. The recovery and reuse abilities of the prepared composite were studied under optimized reaction conditions. The results showed that the 3D-TiO2/BCDs MNPs catalyst has good mechanical and chemical stability during the photo-degradation reaction at least after five runs.
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•Facile hydrothermal synthesis of 3D-TiO2/BCDs MNPs.•High performance of 3D-TiO2/BCDs MNPs for diazinon degradation under sunlight.•Excellent mechanical and chemical stability at least after five runs.
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