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Synthesis of quinazolin-4(3H)-one derivatives using heteropolyacids as heterogeneous and recyclable catalysts
, Article Asian Journal of Chemistry ; Volume 23, Issue 4 , 2011 , Pages 1588-1590 ; 09707077 (ISSN) ; Hashemi, M. M ; Heravi, M. M ; Bamoharram, F. F ; Sharif University of Technology
Abstract
A highly efficient and simple procedure for the synthesis of quinazolin-4(3H)-ones from the condensation of 2-aminobenzamide with triethylorthoesters in presence of a catalytic amounts of heteropolyacids in various solvents is reported
Manganese and cobalt-terephthalate metal-organic frameworks as a precursor for synthesis of Mn2 O3 , Mn3 O4 and Co3 O4 nanoparticles: Active catalysts for olefin heterogeneous oxidation
,
Article
Inorganic Chemistry Communications
;
Volume 61
,
2015
,
Pages 73-76
;
13877003 (ISSN)
; Zare, M
; Bagherzade, M
;
Sharif University of Technology
Elsevier
2015
Abstract
The thermal decomposition of manganese and cobalt-terephthalate Metal-Organic Framework precursors was utilized as a synthetic route for fabrication of Co3 O4 , Mn3 O4 and Mn2 O3 nanoparticles. The prepared metal oxide nanoparticles of Co3 O4 , Mn3 O4 and Mn2 O3 possess average size diameter of 40, 60 and 80 nm respectively. The findings demonstrate that spinel structure nanoparticles of Co3 O4 and Mn3 O4 exhibit efficient catalytic activity toward heterogeneous olefin epoxidation in the presence of tert-butyl hydroperoxide. In...
Zinc oxide as a useful and recyclable catalyst for the one-pot synthesis of 2,4,6-trisubstituted-1,3,5-trioxanes under solvent-free conditions
, Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 28 , 2013 , Pages 9538-9543 ; 08885885 (ISSN) ; Nasr, A. H ; Rabiee, S ; Adibi, E ; Sharif University of Technology
2013
Abstract
Different aliphatic and aromatic aldehydes such as isobutyraldehyde, ethanal, n-propanal, n-butanal, n-hexanal, n-octanal, and substituted benzaldehydes were cyclotrimerized into their corresponding 2,4,6-trialkyl-1,3, 5-trioxanes in the presence of commercial bulk zinc oxide at room temperature under neat conditions within a short span of time with high yield and excellent selectivity. Liquid products were formed as a separate phase and were decanted easily, whereas solid products were isolated by simple extraction. Effect of different additives, mol % of catalyst, kind of substrate, and reaction temperature were examined on the progress of cyclotrimerization reaction
Synthesis of Core-Shell Nanoparticles Supported Iron and Vanadium Schiff Base and Their Application as a Catalyst for Oxidation of Sulfides, Alcohols and Olefins
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this work, synthesized Fe3O4 magnetic nanoparticles andcoated with SiO2 to prepare magnetic core-shell nanoparticles. Then immobilized Schiff baseof iron and vanadium complexes on magnetic core-shell nanoparticles was prepared as a recoverable magnetic nano catalysts. These catalysts were named Fe3O4@SiO2@L1@Fe, Fe3O4@SiO2@L2@Fe and Fe3O4@SiO2@L3@V. Furthermore,olefines epoxidation, sulfides and alcohols oxidation were studied with using iron and vanadium magnetic nano catalysts. The supported catalysts were characterized by atomic absorption, FT-IR and UV–Vis spectra.The catalytic performance of the synthesized iron catalyst was tested for the epoxidation of cyclohexene, styrene and...
Simple methodology for the aerobic N-methylation of substituted anilines catalyzed by zirconium oxychloride octahydrate, ZrOCl2·8H 2O
, Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 32 , 2013 , Pages 11001-11006 ; 08885885 (ISSN) ; Rezaei Seresht, E ; Jafari, F ; Rabiei, S ; Sharif University of Technology
2013
Abstract
A highly chemoselective methodology is described for the N-methylation of functionalized anilines with dimethyl carbonate (MeOCO2Me, DMC) in the presence of ZrOCl2·8H2O. Dimethyl carbonate, which usually promotes methylation at T > 120 C and eventually under inert atmosphere, was activated in the presence of zirconium oxychloride for the desired transformation at 90 C under aerobic conditions. Aminophenols showed good reactivity in this transformation and produced the corresponding N-methylanilines, as the major products, with high selectivity. Catalyst reusability study confirmed that ZrOCl2·8H2O is a recyclable catalyst and its catalytic activity was remained unchanged at least after eight...
A highly reactive and magnetic recyclable catalyst based on silver nanoparticles supported on ferrite for n-monoalkylation of amines with alcohols
, Article Applied Organometallic Chemistry ; Volume 31, Issue 10 , 2017 ; 02682605 (ISSN) ; Shakourian Fard, M ; Nouri, P ; Mahmoodi Hashemi, M ; Sharif University of Technology
Abstract
Fe3O4@SiO2-Ag catalyst was found to be highly active and selective in the N-alkylation of amines with a variety of aromatic and linear alcohols. The heterogeneous nature of the Fe3O4@SiO2-Ag catalyst allows easy recovery and regeneration by applying an external magnet for six subsequent reaction cycles. The prepared catalyst was characterized using electron microscopy techniques, X-ray diffraction, vibrating sample magnetometry and atomic absorption spectroscopy. Copyright © 2017 John Wiley & Sons, Ltd
Nano CoCuFe2O4-catalyzed coupling reaction of arylboronic acid with amines and thiols: An atom-economic and ligand-free route to access unsymmetrical amines and sulfides
, Article Applied Organometallic Chemistry ; Volume 32, Issue 12 , 2018 ; 02682605 (ISSN) ; Pourkaveh, R ; Gholamtajari, M ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
An efficient protocol was developed for the nano CoCuFe2O4-catalyzed C-N and C-S bond formation. By this catalytic system, both amine and sulfide-based structural motifs were formed efficiently in aryl halide-free route. The amination reaction of phenyl boronic acid with various types of amines was conducted under ligand-free conditions, in ethanol as a green solvent at 60°C. Unsymmetrical diaryl/aryl alkyl sulfide synthesis via the coupling reaction of arylboronic acids with thiols was also conducted. The nano cobalt-copper ferrite was used as a heterogenous efficient, inexpensive, magnetically separable and recyclable catalyst that can be used for several cycles. © 2018 John Wiley & Sons,...
Mo(vi) complex supported on Fe3 O4 nanoparticles: magnetically separable nanocatalysts for selective oxidation of sulfides to sulfoxides
,
Article
RSC Advances
;
Volume 5, Issue 66
,
Jun
,
2015
,
Pages 53349-53356
;
20462069 (ISSN)
; Balali, M
; Haghdoost, M. M
; Bagherzadeh, M
;
Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
A molybdenum complex, [MoO2 Cl2 (DMSO)2 ], was immobilized on amino propyl and Schiff base modified magnetic Fe3 O4 @SiO2 nanoparticles by covalent linkage. The resulting nanoparticles were used as efficient and recyclable catalysts for the selective oxidation of sulfides to sulfoxides using urea hydrogen peroxide as the oxidant. The complete characterization of catalysts was carried out by means of thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), elemental analysis, FT-IR and Raman microprobe...
α-Arylation of oxindoles using recyclable metal oxide ferrite nanoparticles: Comparison between the catalytic activities of nickel, cobalt and copper ferrite nanoparticles
, Article Catalysis Communications ; Volume 75 , 2016 , Pages 37-41 ; 15667367 (ISSN) ; Tavakoli, G ; Latifi, F ; Saeednia, B ; Sharif University of Technology
Elsevier
Abstract
Three different spinel metal oxide catalytic systems including NiFe2O4, CuFe2O4 and CoFe2O4 were synthesized using co-precipitation technique and their catalytic activities were compared to each other in α-arylation of oxindole derivatives under the optimized reaction conditions. Both nickel ferrite and copper ferrite magnetic nanoparticles show approximately the same behavior in these reactions but cobalt ferrite ones indicate slightly different properties and were not as good as the other two catalysts. These superparamagnetic catalysts allowed that α-arylation of different types of oxindoles will occur in high yields under mild conditions and at very short times