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1.
One-pot synthesis of substituted chromeno[3,4-b]quinoline derivatives was developed by three-component reaction of aldehydes, dimedone or 1,3-cyclohexadione, and 4-aminocoumarin in the presence of nicotinic acid-supported cobalt ferrite [CoFe2O4@SiO2@Si(CH2)3Cl@NA] as a novel magnetic catalyst in chloroform at reflux conditions. Nicotinic acid-supported cobalt ferrite was characterized via Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, and vibrating sample magnetometry. Moreover, the catalyst could be easily recovered by magnetic separation and recycled up to five times without significant loss of its catalytic activity. The products formed in excellent yields over appropriate reaction times under environmentally friendly conditions. High efficiency and easy isolation of the catalyst from products by simple magnetic attraction are some of the considerable advantages of this procedure. 相似文献
2.
Dadkhoda Ghazanfari Mohammed M. Hashemi Mohammad Reza Akhgar Mohammad Mehdi Foroughi Fariba Najafi-Zadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3018-3022
The ring-opening reaction of epoxides with thiols by SbCl 3 supported on Kieselguhr under solvent-free conditions, afforded high yields of β-hydroxy sulfides. Nucleophilic attack of the thiols occurs regioselectively at the less hindered side of the epoxides. 相似文献
3.
Ali Khalafi-Nezhad Farhad Panahi Somayeh Mohammadi Habib Ollah Foroughi 《Journal of the Iranian Chemical Society》2013,10(2):189-200
Silica boron–sulfuric acid nanoparticles (SBSANs) as a solid Lewis-protic acid have been found to be an efficient heterogeneous catalyst in the synthesis of xanthene and acridine derivatives. The SBSAN-catalyzed reaction between carbonyl compound (aldehyde/ketone/ethyl orthoformate) and 5,5-dimethyl-1,3-cyclohexanedione (dimedone) for synthesis of xanthene derivatives is performed under mild conditions with the excellent isolated yield. Also, we can apply a broad scope of carbonyl compounds and amines for efficient synthesis of various acridine derivatives in the presence of SBSAN catalyst. In these multicomponent approaches the SBSAN catalyst can be reused for several times without any treatment in its catalytic activity. 相似文献
4.
5.
P. Knowles J. Deutsch J. Egger W. Fetscher F. Foroughi J. Govaerts M. Hadri K. Kirch S. Kistryn J. Lang X. Morelle O. Naviliat A. Ninane R. Prieels N. Severijns L. Simons J. Sromicki S. Vandormael P. Van Hove 《Hyperfine Interactions》1999,118(1-4):73-76
Unlike the majority of Michel parameters which are consistent with the Standard Model V-A interaction, the experimental value of ξ″(=0.65±0.36) [1] is poorly known. Our experiment will measure the longitudinal polarization,
P
L
, of positrons emitted from the decay of polarized muons. The value of P
L
, equal to unity in the Standard Model, will decrease for high energy positrons emitted antiparallel to the muon spin if the
combination of Michel parameters ξ″/ξξ′ − 1 deviates from the Standard Model value of zero.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
6.
Synthesis and Cytotoxic Evaluation of Novel 1,2,3‐Triazole‐4‐Linked (2E,6E)‐2‐Benzylidene‐6‐(4‐nitrobenzylidene)cyclohexanones 下载免费PDF全文
Mohammad Mahdavi Maryam Akhbari Mina Saeedi Maryam Karimi Niloufar Foroughi Elahe Karimpour‐Razkenari Heshmatollah Alinezhad Alireza Foroumadi Abbas Shafiee Tahmineh Akbarzadeh 《Helvetica chimica acta》2016,99(3):175-180
This work describes the synthesis of novel 1,2,3‐triazole‐4‐linked (2E,6E)‐2‐benzylidene‐6‐(4‐nitrobenzylidene)cyclo‐hexanones starting from cyclohexanone. 1‐(Cyclohex‐1‐en‐1‐yl)piperidine, the enamine from cyclohexanone and piperidine, reacted with 4‐nitrobenzaldehyde to obtain 2‐(4‐nitrobenzylidene)cyclohexanone. Condensation of the latter compound with (prop‐2‐yn‐1‐yloxy)benzaldehyde derivatives under acidic conditions gave (4‐nitrobenzylidene)‐[(prop‐2‐yn‐1‐yloxy)‐benzylidene]cyclohexanones. Finally, ‘click reaction’ of these derivatives and various organic azides led to the title compounds. All compounds were examined by MTT assay for cytotoxic activity in one human breast cancer cell line, MDA‐MB‐231. 相似文献
7.
F. Foroughi E. Morenzoni T. Prokscha M. Daum K. Deiters D. George D. Herlach C. Petitjean D. Renker V. Vrankovic 《Hyperfine Interactions》2001,138(1-4):483-488
A new project was initiated at PSI to replace the existing μE4 decay channel with a new beam line delivering surface/cloud
beams of highest luminosities. This goal will be accomplished by installing a solenoidal lens system at the main production
target E and then transporting the muons with conventional beamline elements of very big apertures to a greatly enlarged experimental
floor. Several slit systems and an electrostatic separator will be available to control the beam shape and reduce the electrons
and other background.
Particle fluxes up to 5 × 108 μ+/s and 107 μ−/s can be expected at 28 MeV/c beam momentum, using the 600 MeV primary proton beam of 1.7 mA. The operation of the channel
will be limited to a maximum momentum of 40 MeV/c. The beam line has been specially designed to provide highest flux to the
ultra-slow μ+ beam (LEM).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
A series of 1,3-oxazin-6-one derivatives has been synthesized upon treatment of N-unsubstituted amides with chlorocarbonyl phenyl ketene under reflux in toluene for several minutes. In this simple way, 2,5-disubstituted
derivatives of 1,3-oxazin-6-ones have been obtained in high yields. 相似文献
9.
Presence of fracture roughness and occurrence of nonlinear flow complicate fluid flow through rock fractures. This paper presents a qualitative and quantitative study on the effects of fracture wall surface roughness on flow behavior using direct flow simulation on artificial fractures. Previous studies have highlighted the importance of roughness on linear and nonlinear flow through rock fractures. Therefore, considering fracture roughness to propose models for the linear and nonlinear flow parameters seems to be necessary. In the current report, lattice Boltzmann method is used to numerically simulate fluid flow through different fracture realizations. Flow simulations are conducted over a wide range of pressure gradients through each fracture. It is observed that creeping flow at lower pressure gradients can be described using Darcy’s law, while transition to inertial flow occurs at higher pressure gradients. By detecting the onset of inertial flow and regression analysis on the simulation results with Forchheimer equation, inertial resistance coefficients are determined for each fracture. Fracture permeability values are also determined from Darcy flow as well. According to simulation results through different fractures, two parametric expressions are proposed for permeability and inertial resistance coefficient. The proposed models are validated using 3D numerical simulations and experimental results. The results obtained from these two proposed models are further compared with those obtained from the conventional models. The calculated average absolute relative errors and correlation coefficients indicate that the proposed models, despite their simplicity, present acceptable outcomes; the models are also more accurate compared to the available methods in the literature. 相似文献
10.
A highly efficient and green procedure for the large‐scale synthesis of α‐amino nitriles using three‐component condensation of carbonyl compounds, amines, and trimethylsilylcyanide has been developed. Silica boron sulfuric acid nanoparticles (SBSANs) are found as an efficient heterogeneous catalyst for the promotion of this process at room temperature under solvent‐free conditions. This protocol offers an effective and scale‐up procedure for the synthesis of various α‐amino nitriles using a wide range of amines and carbonyl compounds in relatively short reaction time with the excellent isolated yields. In addition, the SBSAN catalyst is easily separated from the reaction mixture by simple filtration and can be reused several times. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:1–8, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21052 相似文献