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101.
Khodabakhsh NIKNAM Mohammad Ali ZOLFIGOL Zahra HOSSIENINEJAD Nader DANESHVAR 《催化学报》2007,28(7):591-595
以金属硫酸氢盐M(HSO4)n(Ca(HSO4)2,Zn(HSO4)2和过硫酸氢钾制剂oxone○R)为催化剂催化醛、1,3-二羰基化合物和尿素进行缩合反应,在90℃及无溶剂的条件下高收率、一锅法合成了3,4-二氢嘧啶-2(1H)-酮. 相似文献
102.
103.
Mohammad Rahimizadeh Mehdi Pordel Mehdi Bakavoli Zahra Bakhtiarpoor Ala Orafaie 《Monatshefte für Chemie / Chemical Monthly》2009,140(6):633-638
Abstract New imidazo[4,5-a]acridone derivatives were synthesized from the rearrangement of 3H-imidazo[4′,5′:3,4]benzo[c]isoxazoles. New imidazo[4,5-a]acridines were obtained from the reaction of imidazo[4,5-a]acridones in boiling POCl3. All of these compounds exhibited antimicrobial activities comparable to streptomycin as reference drug.
Graphical abstract
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104.
Facile and Mild Synthesis and Characterization of Some New Diazo Dyes on the Basis of Schiff Bases in the Presence of Nanocrystalline Magnesium Oxide as a Base Catalyst under Solvent‐free Conditions 下载免费PDF全文
In this research, some new diazo dyes including Schiff base have been synthesized by the condensation reaction between ethylenediamine and derivatives of salicylaldehyde containing diazo functional groups in the presence of nanocrystalline magnesium oxide as a solid base catalyst under solvent‐free conditions. Nanocrystalline magnesium oxide has been characterized by XRD, BJH and TEM techniques. The corresponding products have been obtained in excellent yields and high purity. All of the obtained diazo‐Schiff bases are highly colored and can be applicable as useful diazo dyes and characterized by spectroscopy data. 相似文献
105.
Abdelmalek Zahra Khan Sami Ullah Waqas Hassan Riaz Arshad Khan Israr Ali Tlili Iskander 《Journal of Thermal Analysis and Calorimetry》2021,144(1):205-217
Journal of Thermal Analysis and Calorimetry - The significant bioconvection phenomenon with the utilization of nanoparticles encountered fundamental industrial and technological applications in... 相似文献
106.
Khodayar Gholivand Zahra Hosseini Mehrdad Pourayoubi Zahra Shariatinia 《无机化学与普通化学杂志》2005,631(15):3074-3079
Some new N‐carbonyl, phosphoramidates with formula C6H5C(O)N(H)P(O)R2 (R = NC3H6 ( 1 ), NC6H12 ( 2 ), NHCH2CH=CH2 ( 3 ), N(C3H7)2 ( 4 )) and CCl3C(O)N(H)P(O)R′2 (R′ = NC3H6 ( 5 ), NHCH2CH=CH2 ( 6 )) were synthesized and characterized by 1H, 13C, 31P NMR and IR spectroscopy and elemental analysis. The structures were determined for compounds 1 and 2 . Compound 1 exists as two crystallographically independent molecules in crystal lattice. Both compounds 1 and 2 produced dimeric aggregates via intermolecular ‐P=O…H‐N‐ hydrogen bonds, which in compound 2 is a centrosymmetric dimer. In compounds with four‐membered ring amine groups, 3J(P,C)>2J(P,C), in agreement with our previous studies about five‐membered ring amine groups. Also, 3J(P,C) values in compounds 1 and 5 are greater than in compounds with five‐, six‐ and seven‐membered ring amine groups. 相似文献
107.
Zahra Tabookht Xavier López Coen de Graaf Nathalie Guihéry Nicolas Suaud Nadia Benamor 《Journal of computational chemistry》2012,33(21):1748-1761
The electrical conductivities and plausible charge‐ordering states in the room temperature (r.t.) phase for MMX chains [Ni2(dta)4I]∞ and [Pt2(dta)4I]∞ (dta = CH3CS) have been analyzed with periodic density functional theory (DFT) and correlated ab initio calculations combined with the effective Hamiltonian theory. Periodic DFT calculations show a more delocalized nature of the ground state in [Pt2(dta)4I]∞ compared to [Ni2(dta)4I]∞, which features a rather large energy gap between the occupied and empty bands, and charge polarized dimer units. A larger electrical conductivity for the Pt chain can be expected, especially because the Fermi level lies within a band with contributions from Pt and I orbitals. Electronic structure parameters extracted from ab initio cluster calculations show that the large difference between the observed conductivities at 300 K for Ni and Pt compounds, of 3 orders of magnitude, cannot be explained from the parameters extracted from an embedded M2(dta)4I2 dimer fragment alone. When tetramer fragments are considered, we observe that the interdimer transfer integral (t) between neighboring M2 units connected by an iodine atom at correlated level is comparable in both chains. On the other hand, the energy to transfer an electron from a dimer to the neighboring one (Coulomb repulsion U) is three times larger in the Ni compound with respect to the Pt chain, in line with the poor conductivity of the former. The electronic structure of the M4(dta)8I3 fragment points to an alternate charge‐polarization state for Ni and an average valence state for Pt when the r.t. X‐ray structure is considered. © 2012 Wiley Periodicals, Inc. 相似文献
108.
Fatemeh Saghatchi Ebrahim Ahmadi Zahra Mohamadnia Hassan Hajifatheali Hashem Tabebordbar Farnoosh Karimi 《Chemical Papers》2014,68(11):1555-1560
This study is aimed at atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a novel catalyst. The bis-(2-dodecylsulfanyl-ethyl)-amine (SNS) tridentate ligand with mixed donor atoms was synthesized in high purity using inexpensive reagents and was reacted with copper(I) bromide to produce the CuBr/SNS catalyst. The catalyst mediated living polymerization of MMA yielding polymers with controlled molecular masses and narrow molecular mass distributions (PDI < 1.25). Also, the kinetic plot exhibited a linear increase of ln([M]0/[M]) versus time, indicating constant concentration of propagating radicals during the polymerization. The products were characterized by 1H NMR, 13C NMR, FT-IR, UV-VIS, GC and elemental analyses (CHNS) and by GPC. 相似文献
109.
In this work, acid functionalized multi-wall carbon nanotubes (MWCNTs) were modified with imidazolium-based ionic liquids. The selective oxidation of various alcohols with hydrogen peroxide catalyzed by[PZnMo2W9O39]5-, ZnPOM, supported on ionic liquids-modified with MWCNTs, MWCNTAPIB, is reported. This catalyst[ZnPOM@APIB-MWCNT], was characterized by X-ray diffraction, scanning electron microscopy (SEM) and FT-IR spectroscopic methods. This heterogeneous catalyst exhibited high stability and reusability in the oxidation reaction without loss of its catalytic performance. 相似文献
110.
S.Peyman Zakeri S.Mohammad Moosavi Nejad Mohammadreza Zakeri S.Yaser Ayazi 《中国物理C(英文版)》2018,42(7):073101-073101
In the multi-component configurations of dark matter phenomenology,we propose a minimal twocomponent configuration which is an extension of the Standard Model with only three new fields;one scalar and one fermion interact with the thermal soup through Higgs portal,mediated by the other scalar in such a way that the stabilities of dark matter candidates are made simultaneously by an explicit Z2 symmetry.Against the most common freeze-out framework,we look for dark matter particle signatures in the freeze-in scenario by evaluating the relic density and detection signals.A simple distinguishing feature of the model is the lack of dark matter conversion,so the dark matter components act individually and the model can be adapted entirely to both singlet scalar and singlet fermionic models,separately.We find dark matter self-interaction as the most promising approach to probe such feeble models.Although the scalar component satisfies this constraint,the fermionic one refuses it even in the resonant region. 相似文献