| 1. |
- Ahmadian-Moghaddam, M., et al.
(författare)
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A facile method for regioselective synthesis of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives via N-acetyl/thioacetyl sulfonamide formation
- 2017
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Ingår i: Phosphorus Sulfur and Silicon and the Related Elements. - : Informa UK Limited. - 1042-6507 .- 1563-5325. ; 192:5, s. 481-484
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Tidskriftsartikel (refereegranskat)abstract
- A series of new N-acetyl/thioacetyl-(E)-stilbene benzenesulfonamide derivatives were synthesized regioselectively in moderate to high yields by following a convenient, three-step procedure. The procedure consists of the direct oxidative conversion of a thiol compound to the corresponding sulfonyl chloride using TMSCl/KNO3, followed by a room temperature reaction in a one-pot transformation of the resultant sulfonyl chloride into N-acetyl/thioacetyl sulfonamide, which undergoes a further Pd-catalyzed coupling reaction, giving rise to the stilbene compounds reported for the first time.
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| 2. |
- Arshadi, S., et al.
(författare)
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B-DOPING EFFECT ON THE ADSORPTION OF SOMAN GAS ONTO FULLERENE: A DFT STUDY
- 2015
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Ingår i: Phosphorus Sulfur and Silicon and the Related Elements. - : Informa UK Limited. - 1042-6507 .- 1563-5325. ; 190:11, s. 2051-2061
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Tidskriftsartikel (refereegranskat)abstract
- Density functional theory (DFT) methods were used to investigate the adsorption properties of nerve agent soman (GD), o-pinacolyl methylphosphonofluoridate, on fullerene (C-34) and fullerene doped by boron (FDB). Among the six proposed isomers of fullerene, the most stable one was doped with 1,2-diborol on its five-membered ring moiety. The adsorption energies and equilibrium distances between the different heads of GD molecule and nano-substrates were calculated using basis set superposition error. The total density of state, corrected adsorption energy values, and binding distances signify that GD adsorption happens physically from both O and F heads onto fullerene. When interacting from its F head, GD is physisorbed onto FDB as well. The adsorption of GD on FDB showed the chemical nature when the interaction involves the O and OF heads of GD, suggesting FDB as a potential appropriate adsorbent for this toxic chemical substance.
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| 3. |
- Arshadi, S., et al.
(författare)
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Disiline-doped boron nitride nanotubes: A computational study
- 2014
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Ingår i: Journal of Structural Chemistry. - : Pleiades Publishing Ltd. - 0022-4766 .- 1573-8779. ; 55:4, s. 629-635
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Tidskriftsartikel (refereegranskat)abstract
- The properties of the electronic structure of the Disiline-doped boron nitride nanotubes (Disiline-BNNTs) are investigated by a density functional theory (DFT) calculation. The structural forms are firstly optimized and the CS tensors calculated. Subsequently, the chemical-shielding isotropic (CSI) and chemical shielding anisotropic (CSA) parameters are found. The shielding values of boron (B) and nitrogen (N) atoms were calculated by Gauge-Including Atomic Orbital (GIAO), Continuous Set of Gauge Transformations (CSGT) and Individual Gauges for Atoms in Molecules (IGAIM) methods, using B3LYP/6-311+G*. The B3LYP level of theory with IGAIM was the best method to evaluate the theoretical chemical shifts for studied models. The results reveal a significant effect of Disiline doping on the chemical shielding tensors at the sites of those B-11 and N-15 nuclei located in the nearest neighborhood of the Disiline-doped ring. Furthermore, the values of dipole moments and HOMO-LUMO gaps change in the Disiline-doped models in comparison with the original pristine model.
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| 4. |
- Arshadi, S., et al.
(författare)
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Pure and carbon-doped boron phosphide (6,0) zigzag nanotube: A computational NMR study
- 2015
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Ingår i: Physica B-Condensed Matter. - : Elsevier BV. - 0921-4526. ; 477, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- Calculations were performed for investigation of the properties of the electronic structure of Carbon-Doped Boron Phosphide Nanotube (CDBPNT). Pristine and three models of C-doped structures of (6,0) zigzag BPNT were studied at density functional theory (DFT) in combination with 6-311G* basis set using Gaussian package of program. The calculated parameters reveal that various B-11 and P-31 nuclei are divided into some layers with equivalent electrostatic properties. The electronic structure properties are highly influence(' by replacement of B-11 and P-31 atoms by C-12 atoms in pristine model. Furthermore, the HOMO-LUMO gap energy for suggested doped models (l), (II) and (Ill) were lower than pure BPNT pristine systems. The dipole moment values of models (H) and (Ill) were decreased to 1.788 and 1.789, respectively while the dipole moments of model (l) were enhanced to 4.373, in compare to pure pristine one (2.586). The magnitude of changes in Chemical Shielding (CS) tensor parameters revealed that the electron density at the site of P-31 was higher than that at the sift of B-11 due to carbon doping. (C) 2015 Elsevier B.V. All rights reserved.
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| 5. |
- Bekhradnia, Ahmadreza R., et al.
(författare)
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1,3-dipolar cycloaddition between substituted phenyl azide and 2,3-dihydrofuran
- 2014
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Ingår i: Chemical Papers. - : Springer Science and Business Media LLC. - 0366-6352 .- 1336-9075. ; 68:2, s. 283-290
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Tidskriftsartikel (refereegranskat)abstract
- A theoretical study was performed on the 1,3-dipolar cycloaddition between 2,3-dihydrofuran and substituted phenyl azide using Density Functional Theory (DFT) in combination with a 6-311++G(d,p) basis set. The optimum geometries for reactant, transition state and product, as well as the kinetic data, rate constants and reaction constant (rho) were investigated to rationalise the substitution effects and reaction rates of the 1,3-dipolar cycloaddition process in various solvents. The DFT calculation and Frontier Molecular Orbital (FMO) theory as well as the atomic Fukui indices show that the electron-withdrawing substituents enhance the reaction constant (rho > 0), especially in polar aprotic solvents. Consequently, small changes in the rate constant of the reaction in various solvents and geometric similarity between reactants and transition state structures were suggested as the early transition state mechanism for electron-withdrawing substituents. In addition, the slope of the Hammett plot and susceptibility of the reaction to electron-withdrawing substituents in various solvents confirmed the mechanism. (C) 2013 Institute of Chemistry, Slovak Academy of Sciences
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| 6. |
- Bekhradnia, Ahmadreza R., et al.
(författare)
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New insights into the mechanism of iron-catalyzed cross-coupling reactions
- 2015
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Ingår i: Dalton Transactions. - : Royal Society of Chemistry (RSC). - 1477-9226 .- 1477-9234. ; 44:9, s. 3959-3962
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Tidskriftsartikel (refereegranskat)abstract
- The mechanism of the iron-catalyzed cross-coupling of alkyl halides with aryl Grignard reagents is studied by a combination of GC monitoring and DFT calculation. Herein, we investigate two possible reaction pathways, the regular oxidative addition (OA) pathway and the atom transfer (AT) pathway that might occur in the rate-limiting step. The computational studies revealed that the AT pathway requires less energy than the regular OA pathway.
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