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781.
Microwave‐Assisted Catalyst Free Three Component Synthesis of Mono and Bis Spiro Pyrazolopyridines in Solvent Free Reaction
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Mohammad Nikpassand Leila Zare Fekri Neda Jamshidi 《Journal of heterocyclic chemistry》2015,52(5):1580-1583
Multicomponent synthesis of mono and bis‐spiro pyrazolopyridines from isatin derivatives, indanedione, and 3‐methyl‐5‐aminopyrazole under microwave irradiation in the absence of any catalyst or solvent with high yield and short reaction time is reported. 相似文献
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This paper introduces a simple model for prediction of one electron reduction potential [E(RNO2/R ? NO2–)] of various nitroaryl compounds. The new method uses energy difference between highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in gas phase at the B3LYP/6‐311++G** level (ΔEHOMO‐LUMO) and some structural parameters. It was used for 35 nitroaryl compounds including nitrobenzenes, nitrofurans, 2‐nitroimidazoles, 4‐nitroimidazoles, 5‐ninuintidazoles, nitroazaindoles, nitroacridines, and miscellaneous nitroaryl compounds. The root mean square (rms) percent deviation and the average absolute error of predictions of E(RNO2/R ? NO2–) relative to experiment were decreased from 12.4 % and 0.42 V to 3.5 % and 0.11 V, respectively, upon consideration of several structural parameters. Increment of the value of ΔEHOMO‐LUMO and inclusion of specific polar groups can increase thermodynamic stability of these compounds. 相似文献
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Yonghwi Kim Tao Yang Gyeongwon Yun Mohammad Bagher Ghasemian Jaehyoung Koo Eunsung Lee Sung June Cho Kimoon Kim 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(45):13471-13476
A new approach to the synthesis of hierarchical micro‐ and mesoporous MOFs from microporous MOFs involves a simple hydrolytic post‐synthetic procedure. As a proof of concept, a new microporous MOF, POST‐66(Y), was synthesized and its transformation into a hierarchical micro‐ and mesoporous MOF by water treatment was studied. This method produced mesopores in the range of 3 to 20 nm in the MOF while maintaining the original microporous structure, at least in part. The degree of micro‐ and mesoporosity can be controlled by adjusting the time and temperature of hydrolysis. The resulting hierarchical porous MOF, POST‐66(Y)‐wt, can be utilized to encapsulate nanometer‐sized guests such as proteins, and the enhanced stability and recyclability of an encapsulated enzyme is demonstrated. 相似文献
785.
Influence of thermal annealing on the structural and optical properties of maghemite (γ‐Fe2O3) nanoparticle thin films
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Ehsan Parsianpour Mohammad Gholami Nima Shahbazi Feridoun Samavat 《Surface and interface analysis : SIA》2015,47(5):612-617
In this study, maghemite (γ‐Fe2O3) nanoparticles were initially synthesized via chemical co‐precipitation and then deposited by spray pyrolysis as thin films on white glass substrates. The thin films were annealed for 8 h at 400, 450, 500, 550, and 600 °C in an oven. The structural studies of maghemite nanoparticles were carried out using X‐ray diffractometer. Structural properties that we investigated by X‐ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, SEM, and Energy dispersive X‐ray analysis (EDS). Optical properties of the samples were also investigated by ultraviolet‐visible (UV–vis) spectroscopy. The results showed that maghemite nanoparticles have crystalline structure with domain that increases in size with increasing annealing temperature. The optical band gap values were found to reduce from 2.9 to 2.4 eV with increase in annealing temperature. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Mahdi Mirzaei Hossein Eshghi Mohammad Rahimizadeh Mehdi Bakavoli Maryam M. Matin Minoo Hosseinymehr Hadi Amiri Rudbari Giuseppe Bruno 《中国化学会会志》2015,62(12):1087-1096
A series of α‐aminophosphonates were synthesized through one‐pot condensation of aryl aldehydes, aryl amines and diethyl phosphite in the absence of any catalyst and organic solvents. All the synthesized α‐aminophosphonates were characterized by spectral and elemental analysis and in the case of compound 4j by X‐ray crystallography. Some of these new α‐aminophosphonate derivatives were found to have cytotoxic activity on the cancer cell line DU145 in vitro by the MTT method. 相似文献