排序方式: 共有187条查询结果,搜索用时 15 毫秒
51.
Maryam Rahimi Reza Ghiasi Jamaat Parisa Rajabali 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(1):125-133
Russian Journal of Physical Chemistry A - This study investigates the effect of different substituents on the isomerization reaction of the [(η5‑C5H5)(CO)(Me)Re≡CC6H5] carbyne... 相似文献
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A moisture‐ and air‐stable heterogenized palladium catalyst was synthesized by coordination of palladium with S‐propyl‐2‐aminothiobenzamide supported on Fe3O4 magnetic nanoparticles. The prepared nanocatalyst was characterized using Fourier transform infrared, energy‐dispersive X‐ray and inductively coupled plasma atomic emission spectroscopies, X‐ray diffraction, vibrating sample magnetometry, transmission and scanning electron microscopies, dynamic laser scattering and thermogravimetric analysis. This catalyst could be dispersed homogeneously in water or poly(ethylene glycol) and further applied as an excellent nano‐organometal catalyst for Suzuki and Heck reactions. The catalyst was easily separated with the assistance of an external magnet from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency or palladium leaching. The leaching of catalyst was examined using hot filtration and inductively coupled plasma atomic emission spectroscopy. Also, the effects of various reaction parameters on the Suzuki and Heck reactions are discussed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Ghodsi Mohammadi Ziarani Alireza Badiei Zeinab Dashtianeh Parisa Gholamzadeh Nina Hosseini Mohtasham 《Research on Chemical Intermediates》2013,39(7):3157-3163
Sulfonic-acid-functionalized silica was applied as an efficient heterogeneous acid catalyst in the Ritter reaction to prepare amides by reaction of various benzylic, allylic, and tertiary alcohols with various nitriles in good to excellent yields under solvent-free conditions. The simplicity of the reaction, recovery of catalyst without loss of reactivity, high yield of products, and short reaction time represent improvements over many existing methods. 相似文献
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NaBH4/Ac2O/DOWEX(R)50WX4: A Convenient System for Fast Preparation of gem‐Diacetates from Aldehydes 下载免费PDF全文
Reductive‐acylalation of aldehydes has been carried out by NaBH4/Ac2O/DOWEX(R)50WX4 system. A variety of aldehydes (1 mmol) have been reacted with Ac2O (0.5 mL) and NaBH4 (1 mmol) in the presence of DOWEX(R)50WX4 (0.5 g) for the preparation of their corresponding acylals within 1 min at room temperature with excellent yields of the products (90‐95%). Ketones do not react with this system. 相似文献
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Ali Reza Noori Saman Hosseinkhani Parisa Ghiasi Jafar Akbari Akbar Heydari 《Applied biochemistry and biotechnology》2014,172(6):3116-3127
Ionic liquids as neoteric solvents, microwave irradiation, and alternative energy source are becoming as a solvent for many enzymatic reactions. We recently showed that the incubation of firefly luciferase from Photinus pyralis with various ionic liquids increased the activity and stability of luciferase. Magnetic nanoparticles supported ionic liquids have been obtained by covalent bonding of ionic liquids-silane on magnetic silica nanoparticles. In the present study, the effects of [γ-Fe2O3@SiO2][BMImCl] and [γ-Fe2O3@SiO2][BMImI] were investigated on the structural properties and function of luciferase using circular dichroism, fluorescence spectroscopy, and bioluminescence assay. Enzyme activity and structural stability increased in the presence of magnetic nanoparticles supported ionic liquids. Furthermore, the effect of ingredients which were used was not considerable on K m value of luciferase for adenosine-5′-triphosphate and also K m value for luciferin. 相似文献
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Bahram Ghanbari Parisa Gholamnezhad Mojgan Hatami 《Journal of Thermal Analysis and Calorimetry》2014,118(3):1631-1637
A simple method for the formation of inclusion complex of [60]fullerene with two O2N2-donor aza-crown macrocyclic ligands was introduced. The products were characterized using UV–vis and IR spectroscopies as well as HPLC, and ESI mass spectrometry. The ESI mass and elemental analysis data revealed that the ratio of macroring:[60]fullerene were not the same. The binding capability of the macrorings as well as the number of the macroring addends to [60]fullerene were investigated using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Considering percentage mass loss in different steps of TG and the enthalpy changes in DSC found for each of these products, the number of their addends on [60]fullerene were calculated. Theoretical calculations in semi-empirical level using AM1 suggested that proper orientation of the nitrogen-donor groups on the aza-crown macrorings toward [60]fullerene could be the main factor for the observed difference in the number of macroring addends attached to [60]fullerene. 相似文献
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Khosrow Jadidi Ramin Ghahremanzadeh Davoud Asgari Parisa Eslami Hamid Arvin-Nezhad 《Monatshefte für Chemie / Chemical Monthly》2008,141(7):1229-1232
The green reaction of isatoic anhydrides with α-amino acids in presence of the ionic liquid 1-butyl-3-methylimidazolium bromide
afforded 1,4-benzodiazepine-2,5-diones in excellent yields in absence of a catalyst. The reaction workup is simple and the
ionic liquid was easily recovered from the reaction and reused. The methodology was quite general and a range of cyclic and
acyclic α-amino acids were examined to produce 1,4-benzodiazepine-2,5-diones. 相似文献
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Khosrow Jadidi Ramin Ghahremanzadeh Davoud Asgari Parisa Eslami Hamid Arvin-Nezhad 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1229-1232
The green reaction of isatoic anhydrides with α-amino acids in presence of the ionic liquid 1-butyl-3-methylimidazolium bromide
afforded 1,4-benzodiazepine-2,5-diones in excellent yields in absence of a catalyst. The reaction workup is simple and the
ionic liquid was easily recovered from the reaction and reused. The methodology was quite general and a range of cyclic and
acyclic α-amino acids were examined to produce 1,4-benzodiazepine-2,5-diones.
Correspondence: Khosrow Jadidi, Department of Chemistry, Shahid Beheshti University, PO Box 1983963113, Tehran, Iran. 相似文献