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Facile double Fries rearrangement of diesters under microwave irradiation; application to the synthesis of a biogenetically rare type of natural phenol
, Article Letters in Organic Chemistry ; Volume 3, Issue 2 , 2006 , Pages 123-127 ; 15701786 (ISSN) ; Porkaleh, H ; Zali Boeini, H ; Sharif University of Technology
2006
Abstract
Various diesters successfully undergo a double Fries rearrangement to afford the corresponding bis o-hydroxylaryl ketones, in the presence of AlCl3 under microwave irradiation. © 2006 Bentham Science Publishers Ltd
A novel and simple solvent free method for nucleophilic aromatic substitution of inactive aryl halides
, Article Synthetic Communications ; Volume 34, Issue 15 , 2004 , Pages 2783-2787 ; 00397911 (ISSN) ; Akhbari, M ; Sharif University of Technology
2004
Abstract
A simple, high yield, and short time method for nucleophilic displacement reaction of inactive aryl halides is reported. The reaction is performed in microwave oven under thermal condition with montmorillonite supported AgNO 3
A new protocol for O-methylation of phenolic compounds with trimethyl phosphite or trimethyl phosphate under solvent-free condition and microwave irradiation
, Article Phosphorus, Sulfur and Silicon and the Related Elements ; Volume 178, Issue 11 , 2003 , Pages 2343-2348 ; 10426507 (ISSN) ; Rajabi, F ; Sharif University of Technology
Taylor and Francis Ltd
2003
Abstract
A simple method for the preparation of industrially important alkyl aryl ethers is reported. Several phenolic compounds such as phenols, naphthols, and hydroxy coumarins were O-methylated with trimethyl phosphite or trimethyl phosphate under microwave irradiation and solvent-free condition in almost quantitative yields. Reaction of 2-naphthol with trimethyl phosphate gave mixture of 2-methoxynaphthalene and 1-methyl-2-methoxynaphthalene while the reaction with trimethyl phosphite gave mostly 2-methoxynaphthalene. This method is highly efficient for the methylating of phenolic compounds with very easy experimental procedure and environmental friendly conditions
Activation of CX (=Cl, Br) bond in aryl halides toward the palladium-catalyzed Heck reaction using 2,6-bis(diphenylphosphino)pyridine
, Article Journal of Molecular Catalysis A: Chemical ; Volume 366 , January , 2013 , Pages 30-35 ; 13811169 (ISSN) ; Nadri, S ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
2013
Abstract
The 2,6-bis(diphenylphosphino)pyridine/palladium catalytic system successfully catalyzes the Heck coupling reaction of less reactive aryl chlorides as well as aryl bromides with styrene to give the corresponding olefins in reasonable yields. TBAB (tetrabutylammoniumbromide) as an additive was found to be essential for these reactions. The results of Heck reaction exhibited a high selectivity (>99/1) favoring the trans product
Immobilized palladium nanoparticles on silica functionalized N-propylpiperazine sodium N-propionate (SBPPSP): Catalytic activity evaluation in copper-free Sonogashira reaction
, Article Journal of the Iranian Chemical Society ; Volume 10, Issue 6 , 2013 , Pages 1291-1296 ; 1735207X (ISSN) ; Deris, A ; Panahi, F ; Hormozi Nezhad, M. R ; Sharif University of Technology
2013
Abstract
An efficient heterogeneous palladium catalyst system has been developed based on immobilization of Pd nanoparticles on silica-bonded N-propylpiperazine sodium N-propionate (SBPPSP) substrate. SBPPSP substrate can stabilize the Pd nanoparticles effectively so that it can improve their stability against aggregation. In addition, grafted piperazine species on to the silica backbone prevent the removing of Pd nanoparticles from the substrate surface. Transmission electron microscopy (TEM) of catalyst is shown the size of Pd nanoparticles, also it confirmed by particle size analyzer which shown the average size of 21 nm for Pd. The catalytic activity of these catalysts was investigated in the...
Modification of silica using piperazine for immobilization of palladium nanoparticles: A study of its catalytic activity as an efficient heterogeneous catalyst for Heck and Suzuki reactions
, Article Journal of the Iranian Chemical Society ; Volume 10, Issue 3 , 2013 , Pages 527-534 ; 1735207X (ISSN) ; Habibabad, M. S ; Deris, A ; Panahi, F ; Reza Hormozi Nezhad, M ; Sharif University of Technology
2013
Abstract
An efficient heterogeneous palladium catalyst system has been developed based on immobilization of Pd nanoparticles on silica-bonded N-propylpiperazine (SBNPP) substrate. SBNPP substrate can stabilize the Pd nanoparticles effectively so that it can improve their stability against aggregation. Also, grafted piperazine species onto the silica backbone prevents the removing of Pd nanoparticles from the substrate surface. It seems that the high recyclable capability of Pd-SBNPP catalysts is resulted from these two characteristics. Transmission electron microscopy (TEM) of catalyst is shown the size of Pd nanoparticles in Pd-SBNPP average of 20 nm. Furthermore, X-ray photoelectron spectroscopy...
Nano-TiO2: An eco-friendly and re-usable catalyst for the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes
, Article Journal of the Iranian Chemical Society ; Volume 8, Issue SUPPL. 1 , February , 2011 , Pages S129-S134 ; 1735207X (ISSN) ; Bamoniri, A ; Akbari, A ; Taghavinia, N ; Sharif University of Technology
2011
Abstract
Synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes using nano-TiO 2 as eco-friendly and efficient catalyst is reported. Short reaction times, high yields, a clean process, simple methodology, easy work-up and green conditions are advantages of this protocol
Microwave-promoted pseudo-thia-Fries rearrangement of aryl benzylsulfonates; highly reactive benzyl cation generation
, Article Journal of Sulfur Chemistry ; Volume 25, Issue 2-3 , 2004 , Pages 125-130 ; 17415993 (ISSN) ; Hoor, A. A ; Dekamin, M. G ; Sharif University of Technology
2004
Abstract
Aryl benzylsulfonates undergo so-called pseudo-thia-Fries rearrangement under microwave irradiation. Benzylated phenolic compounds have been obtained with the loss of 'SO2' from the starting materials
FeCl3 as an efficient and new catalyst for the thia-Fries rearrangement of aryl sulfinates
, Article Tetrahedron Letters ; Volume 42, Issue 45 , 2001 , Pages 8119-8121 ; 00404039 (ISSN) ; Dekamin, M. G ; Ghaffarzadeh, M ; Sharif University of Technology
2001
Abstract
Aryl arenesulfinates rearrange to the corresponding arenesulfinyl phenols via a thia-Fries rearrangement on catalysis by anhydrous FeCl3 in dry dichloromethane at room temperature in good to excellent yields. © 2001 Published by Elsevier Science Ltd
In situ generation of highly active bis(N-heterocyclic)carbene palladium as an efficient catalyst in direct S-arylation of methylphenyl sulfoxide and the Heck reaction: Ligand steric effects in product selectivity
, Article Applied Organometallic Chemistry ; 2016 ; 02682605 (ISSN) ; Mousavi, N ; Jamali, S ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
The use of 1,3-bis(N-heterocyclic)carbene ligands with different alkyl wingtip groups (alkyl = methyl, isopropyl and tert-butyl) is an effective method for the palladium-catalysed direct S-arylation of methylphenyl sulfoxide and C-C coupling of various of aryl halides with alkenes. The reactions proceed in moderate to good yields. Interestingly, it is shown experimentally that, by using bulkier bidentate N-heterocyclic carbene ligands, more selective catalytic systems towards cis products in Heck coupling reactions can be achieved
In situ generation of highly active bis(N-heterocyclic)carbene palladium as an efficient catalyst in direct S-arylation of methylphenyl sulfoxide and the Heck reaction: Ligand steric effects in product selectivity
, Article Applied Organometallic Chemistry ; Volume 31, Issue 8 , 2017 ; 02682605 (ISSN) ; Mousavi, N. A ; Jamali, S ; Sharif University of Technology
John Wiley and Sons Ltd
2017
Abstract
The use of 1,3-bis(N-heterocyclic)carbene ligands with different alkyl wingtip groups (alkyl = methyl, isopropyl and tert-butyl) is an effective method for the palladium-catalysed direct S-arylation of methylphenyl sulfoxide and C–C coupling of various of aryl halides with alkenes. The reactions proceed in moderate to good yields. Interestingly, it is shown experimentally that, by using bulkier bidentate N-heterocyclic carbene ligands, more selective catalytic systems towards cis products in Heck coupling reactions can be achieved. Copyright © 2016 John Wiley & Sons, Ltd
Synthesis of fulvene vinyl ethers by gold catalysis
, Article Chemistry - A European Journal ; Volume 26, Issue 23 , 2020 , Pages 5280-5287 ; Schwarz, J ; Lustosa, D. M ; Pourkaveh, R ; Hoffmann, M ; Rominger, F ; Rudolph, M ; Dreuw, A ; Hashmi, A. S. K ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Gold-catalyzed cyclization of 1,5-diynes with ketones as reagents and solvent provides diversely substituted vinyl ethers under mild conditions. The regioselectivity of such gold-catalyzed cyclizations is usually controlled by the scaffold of the diyne. Herein, we report the first solvent-controlled switching of regioselectivity from a 6-endo-dig- to 5-endo-dig-cyclization in these transformations, providing fulvene derivatives. With respect to the functional-group tolerance, aryl fluorides, chlorides, bromides, and ethers are tolerated. Furthermore, the mechanism and selectivity are put to scrutiny by experimental studies and a thermodynamic analysis of the product. Additionally,...
Synthesis of new 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes via Vilsmeier-Haack reaction
, Article Journal of Heterocyclic Chemistry ; Volume 47, Issue 2 , 2010 , Pages 463-467 ; 0022152X (ISSN) ; Zirak, M ; Akbari, A ; Hashemi, M. M ; Sharif University of Technology
2010
Abstract
(Chemical Equation Presented) New 2-aryl-4-chloro-3-hydroxy-1H-indole-5,7- dicarbaldehydes were synthesized in three steps from acetophenone derivatives. By oxidation of acetophenones to aryl glyoxals using selenium dioxide and condensation with acetylacetone in the presence of ammonium acetate in water 3-acetyl-5-aryl-4-hydroxy-2-methyl-1H-pyrrols were obtained. 2-Aryl-4-chloro-3-hydroxy-1H-indole-5,7-dicarbaldehydes were synthesized via Vilsmeier-Haack reaction of pyrrole derivatives in moderate yields
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
Synthesis of Pincer Palladium Complexes and Molybdenium, Gold and Platinum Complexes Containing Azulene Based Ligands: Catalytic and Optical Properties Studies
, Ph.D. Dissertation Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor) ; Jamali, Sirous (Supervisor)
Abstract
There are two parts in this thesis. The first one is about the synthesis of azulene based compounds, which are characterized by 13C and 1H NMR. These compounds were included in three imine ligands (1,2 and 3) and a NHC ligand (4). Azulene based materials shows a fluorescence emission. The stimuli-responsive emissive azulene derivatives are very rare. herein, we report the synthesis of stimuli responsive emissive 1- and 1,3-disubstitution azulene-based compounds that can switch on and off the emission upon protonation with trifluoroacetic acid (TFAH) and deprotonation with triethylamine respectively. The type of transitions were studied by computational calculations. The complexation of some...
Pd(OAc)2 without added ligand as an active catalyst for Mizoroki-Heck reaction in aqueous media
, Article RSC Advances ; Volume 2, Issue 32 , 2012 , Pages 12091-12095 ; 20462069 (ISSN) ; Bagherzadeh, M ; Moradi Shoeili, Z ; Boghaei, D. M ; Sharif University of Technology
2012
Abstract
Conditions for an efficient ligand-free Heck C-C coupling reaction of aryl iodides and bromides with terminal olefins under aerobic conditions have been developed. Critical to the success of this new protocol is the use of palladium acetate as an extremely active catalyst for the Heck reaction in water and aqueous media. Both the base and the solvent were found to have a fundamental influence on the efficiency of the reaction, with K2CO3 and a mixture of (2:1) H2O/DMSO being the optimal base and solvent, respectively
Copper(II) acetate
, Article Synlett ; Volume 23, Issue 13 , 2012 , Pages 1995-1996 ; 09365214 (ISSN) ; Sharif University of Technology
2012
Abstract
(A) Chakraborty and co-workers have developed a green method for the bulk ring-opening polymerization of lactides in the presence of Cu(OAc)2 as a good catalyst to synthesize polymers with different end-terminal groups.3 These polymerizations are highly controlled leading to the formation of polymers with the expected number of average molecular weights and narrow molecular weight distribution. (B) Garden and co-workers have found that the oxidative addition of anilines with 1,4-naphthoquinone to give N-aryl-2-amino-1,4-naphthoquinones can be performed in the presence of catalytic amounts of copper(II) acetate.4 All the reactions are generally more efficient in that they are cleaner, higher...
A diastereo and chemo selective synthesis of 6-amino-4-aryl-3-oxo-2,3,3a,4-tetrahydro-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile under environmentally benevolent conditions
, Article Journal of Molecular Structure ; Volume 1257 , 2022 ; 00222860 (ISSN) ; Eslami, M ; Aghamiri, B ; Sharif University of Technology
Elsevier B.V
2022
Abstract
We have developed an environmentally friendly benign and practical protocol for the highly diastereo and chemo selective synthesis of some novel derivatives of 6-amino-4-aryl-3-oxo-2,3,3a,4-tetrahydro-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile via a one-pot three-component reaction between arylaldehydes, malononitrile and 3-amino-1H-pyrazol-5(4H)-one in the presence of acetic acid as a catalyst and aqueous green medium at the ambient temperature. In this synthetic protocol, we highlight the utility of enaminone functional groups of 3-amino-1H-pyrazol-5(4H)-one for the synthesis of N-cyclized pyrazolone fused 3,4-dihydropyridine skeletons. Some important features of this new synthetic green...
2,6-Bis(diphenylphosphino)pyridine: A simple ligand showing high performance in palladium-catalyzed CN coupling reactions
, Article Tetrahedron Letters ; Vol. 55, issue. 30 , July , 2014 , p. 4098-4101 ; ISSN: 00404039 ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
Abstract
The use of commercially available 2,6-bis(diphenylphosphino)pyridine as a ligand in conjunction with K2CO3, DMAc and TBAB is an effective method for the palladium-catalyzed CN coupling of a variety of aryl halides with anilines, N-heterocyclic aromatic amines, and a cyclic secondary amine. The reactions proceed in good to excellent yield (up to 98%) while the loading of Pd(OAc)2 was as low as 0.025 mol %
Chemometrics-assisted effect-directed analysis of crude and refined oil using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry
, Article Environmental Science and Technology ; Vol. 48, issue. 5 , 2014 , pp. 3074-3083 ; ISSN: 0013936X ; Thomas, K. V ; Parastar, H ; Diez, S ; Tauler, R ; Bayona, J. M ; Sharif University of Technology
Abstract
An effect-directed analysis (EDA) of fresh and artificially weathered (evaporated, photooxidized) samples of North Sea crude oil and residual heavy fuel oil is presented. Aliphatic, aromatic, and polar oil fractions were tested for the presence of aryl hydrocarbon receptor (AhR) agonist and androgen receptor (AR) antagonist, demonstrating for the first time the AR antagonist effects in the aromatic and, to a lesser extent, polar fractions. An extension of the typical EDA strategy to include an N-way partial least-squares (N-PLS) model capable of relating the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOFMS) data set to the bioassay data...