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A one-pot, three-component, Mannich condensation of electron-rich aromatic compounds such as 5-methyl-2-hydroxyphenyl sulfide, 2-aminopyrimidine, and various aromatic aldehydes were used to prepare a series of new unsymmetrical multidentate aminophenol ligands. These compounds were synthesized in solvent-free conditions as a fast, simple, convenient, and uncatalyzed method. Details of the reaction conditions are discussed. 相似文献
103.
Tabani Zaniar Maghsoudi Hafez Fathollahi Zonouz Abolfazl 《Journal of Solid State Electrochemistry》2021,25(2):651-657
Journal of Solid State Electrochemistry - Polyvinylidene fluoride (PVDF) porous membranes were prepared by non-solvent-induced phase separation (NIPS) method. The membranes were made by different... 相似文献
104.
A simple and efficient procedure for the synthesis of symmetrical bis-Schiff bases has been described that employs a condensation reaction of symmetrical primary bis-amine of 5,5′-methylenebis(2-aminothiazole) with a series of aromatic aldehyde derivatives under solvent-free conditions at elevated temperature. The advantages of these reactions are simplicity of the reaction procedure, short reaction times, simple workup, catalyst-free conditions, and pure products in good to excellent yields. Details of the reaction conditions are discussed. 相似文献
105.
Ghandi M Bozcheloei AH Nazari SH Sadeghzadeh M 《The Journal of organic chemistry》2011,76(24):9975-9982
We have developed a solvent-dependent method for the synthesis of novel benzo-δ-sultone scaffolds. A variety of benzylbenzo[e][1,2]oxathiin-4(3H)-one-2,2-dioxides were obtained in high yields in DMF using a one-pot, DBU-catalyzed condensation of 2-hydroxybenzaldehydes with a number of (E)-2-phenylethenesulfonyl chlorides. On the other hand, the initially prepared 2-formylphenyl-(E)-2-phenylethenesulfonate derivatives underwent DBU-catalyzed reactions to a series of 3-[methoxy(phenyl)methyl]benzo[e][1,2]oxathiine-2,2-dioxides in moderate to good yields in MeOH. These reactions presumably proceed via DBU-catalyzed O-sulfonylation/intramolecular Baylis-Hillman/1,3-H shift or dehydration tandem sequences, respectively. 相似文献
106.
We propose a new fast scalable method for achieving a two-qubit entangling gate between arbitrary distant qubits in a network by exploiting dispersionless propagation in uniform chains. This is achieved dynamically by switching on a strong interaction between the qubits and a bus formed by a nonengineered chain of interacting qubits. The quality of the gate scales very efficiently with qubit separations. Surprisingly, a sudden switching of the couplings is not necessary. Moreover, our gate mechanism works for multiple gate operations without resetting the bus. We propose a possible experimental realization in cold atoms trapped in optical lattices and near field Fresnel trapping potentials. 相似文献
107.
Abolfazl Mohebbi Arjomand Mehrabani-Zeinabad Mohammadhossein Navid-Famili 《Polymer Science Series A》2011,53(11):1076-1085
In this study, dynamic behaviour of nucleation was investigated during foaming process of polystyrene in presence of nano aluminium oxide. Nano aluminium oxide played a role of a bubble nucleating agent within polystyrene matrix. Foaming process was visually observed in conjunction with supercritical N2. Furthermore, the effect of nano Al2O3 compositions on the growth rate was studied. Also, final density per unit area and the average size in the latest growth steps were assessed. The obtained data were compared with foaming process for unfilled polystyrene under the same conditions. The results demonstrated that the final sizes of bubbles as well as the average cell density of the foam were reduced by using of nucleating agent. The growth rate of bubbles was also decreased by increasing the nano Al2O3 particles content. In addition, influence of temperature on foam density of nanocomposite specimens was greater than unfilled polystyrene foam. In presence of nano particle, the cell density was uniformly distributed in nanocomposites specimens. The article is published in the original. 相似文献
108.
Noruzian Fatemeh Olyaei Abolfazl Hajinasiri Rahimeh 《Research on Chemical Intermediates》2019,45(9):4383-4394
Research on Chemical Intermediates - A catalyst-free, simple and green protocol has been accomplished for the synthesis of novel 1H-furo[2,3-c]pyrazole-4-amines in a one-pot four-component domino... 相似文献
109.
In this paper, the effect of the simultaneous rotation of the carboxyl (COOH) and ester (R'COOR) functional groups on the potential energy surface (PES) of aspirin is studied. Relative energies are reported at the HF/aug-cc-pVDZ and B3LYP/aug-cc-pVDZ levels of theory. To understand the activity and selected electrophilic attack sites, electric dipole moments, atomic charges, HOMO-LUMO energy gap, natural bond orbital (NBO), and molecular electrostatic potential (MEP) analyses, as well as the main structural parameters of the identified conformers, are studied at the same theoretical level. Finally, an NBO analysis is used to demonstrate charge transfer between lone pairs and localized bonds. 相似文献
110.
Ehsan Zahedi Majid Mozaffari Farzaneh Shahsavar Abolfazl Shiroudi Michael S. Deleuze 《Research on Chemical Intermediates》2017,43(3):1575-1590
The cheletropic elimination process of N2 from (2,5-dihydro-1H-pyrrol-1-ium-1-ylidene) amide (C4H6N2) has been studied computationally using density functional theory, along with the M06-2X/aug-cc-pVTZ level of theory. The calculated energy profile has been supplemented with calculations of kinetic rate constants using transition state theory (TST) and statistical Rice–Ramsperger–Kassel–Marcus (RRKM) theory. This elimination process takes place spontaneously with an activation energy around 33 kJ/mol. Pressure dependence of the rate constants revealed that the TST approximation breaks down and fall-off expression is necessary for the kinetic modeling. At temperatures ranging from 240 to 360 K and atmospheric pressure, the unimolecular rate constant is evaluated from RRKM theory as \(k_{{(240 - 360\,{\text{K}})}}^{{1.0{\text{atm}}}} = 1.0249 \times 10^{12} \times {\text{e}}^{{ - \frac{{33.11\;{\text{kJ}}/{\text{mol}}}}{RT}}} \,{\text{s}}^{ - 1}\). Bonding changes along the reaction coordinate have been studied using bonding evolution theory. Electron localization function topological analysis reveals that the cheletropic elimination is characterized topologically by four successive structural stability domains (SSDs). Breaking of C–N bonds (Rx = 0.1992 amu1/2 Bohr) and the other selected points separating the SSDs along the reaction coordinate occur in the vicinity of the transition state. 相似文献