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LiClO4 · 3H2O promoted highly regioselective ring-opening of epoxides with thiols under neutral conditions [electronic resource]
, Article Catalysis Communications ; 2006, Volume 7, Issue 4, Pages 224–227 ; Saidi, M. R ; Sharif University of Technology
Abstract
A simple, rapid, atom economy and highly efficient procedure has been developed for thiolysis of epoxides by aromatic and aliphatic thiols under solvent-free conditions. A high regioselectivity in favor of nucleophilic attack at the benzylic carbon atom of aromatic epoxides, such as styrene oxide, is observed. However, aliphatic unsymmetrical alkenyl oxides undergo selective nucleophilic attack at the sterically less hindered carbon atom. A variety of β-hydroxy sulfides were obtained in short reaction time and excellent yields with nearly complete regioselectivity
Microwave assisted preparation of flavylium salts with perchloric acid impregnated on silica gel under solvent-free conditions
, Article Letters in Organic Chemistry ; Vol. 11, issue. 10 , 2014 , pp. 713-718 ; ISSN: 15701786 ; Foroushani, B. K ; Ghonouei, N ; Kalahroodi, E. L ; Sharif University of Technology
Abstract
Perchloric acid immobilized on silica gel (SiO2-HClO4) has been utilized as a mild and cheap reagent for onepot preparation of different varieties of flavylium salts via tandem reaction of different acetophenones with Salicylaldehydes under solvent-free conditions. Different reaction conditions such as conventional heating and microwave irradiation have been investigated. The corresponding flavylium salts have been prepared in high yields. The procedure is milder and more convenient than the known procedures
Lithium perchlorate mediated three-component preparation of α-aminonitriles under solvent-free conditions
, Article Synthetic Communications ; Volume 34, Issue 7 , 2004 , Pages 1207-1214 ; 00397911 (ISSN) ; Saidi, M. R ; Sharif University of Technology
2004
Abstract
A three-component reaction between aliphatic or aromatic aldehyde, an amine and trimethylsilyl cyanide mediated by solid LiClO4, gave amino nitriles in good to excellent yields. The reaction proceeded smoothly under solvent-free conditions without any side products
Microwave assisted reduction of Schiff bases by triethylammonium formate/formic acid system
, Article Journal of Chemical Research - Part S ; Issue 12 , 2001 , Pages 525-527 ; 03082342 (ISSN) ; Khakshoor, O ; Ghaffarzadeh, M ; Sharif University of Technology
2001
Abstract
Aryl schiff bases were efficiently reduced to the corresponding secondry amines by triethylammonium formate/formic acid system under microwave irradiation in solvent-free condition
Optimization of catalytic activity of sulfated titania for efficient synthesis of isoamyl acetate by response surface methodology
, Article Monatshefte fur Chemie ; Volume 146, Issue 12 , December , 2015 , Pages 1949-1957 ; 00269247 (ISSN) ; Sadehvand, M ; Azad, A ; Dekamin, M. G ; Jalali Heravi, M ; Mollahosseini, A ; Amani, M ; Tadjarodi, A ; Sharif University of Technology
Springer-Verlag Wien
2015
Abstract
TiO2 nanoparticles were synthesized by sol-gel method using titanium tetraisopropoxide. Sulfate ions were introduced on the titania by impregnation method using sulfuric acid as precursor of sulfate ions. Fourier transform infrared and energy-dispersive X-ray spectroscopy, X-ray fluorescence as well as X-ray diffraction, scanning electron microscopy, and BET methods were used for the characterization of the obtained nanoparticles. The esterification of isoamyl alcohol with acetic acid was investigated to prove the catalytic activity of the TiO2 nanoparticles under solvent-free conditions. Response surface methodology was applied to optimize the effect of some parameters such as the molar...
BF3.SiO2: An efficient heterogeneous alternative for regio-chemo and stereoselective Claisen-Schmidt condensation
, Article Journal of the Iranian Chemical Society ; Volume 5, Issue 4 , 2008 , Pages 694-698 ; 1735207X (ISSN) ; Mirjalili, B. F ; Hashemi, M. M ; Sharif University of Technology
Iranian Chemical Society
2008
Abstract
Under solvent free conditions between 40-50 °C, BF3.SiO 2, a mild solid acid catalyst, is applied to regio-chemo and stereoselective Claisen-Schmidt condensation. The procedure is very simple and the products are isolated with an easy workup in good to excellent yields
Stereoselective synthesis of β-amino ketones via direct Mannich-type reactions, catalyzed with ZrOCl2·8H2O under solvent-free conditions
, Article European Journal of Organic Chemistry ; Issue 22 , 2006 , Pages 5152-5157 ; 1434193X (ISSN) ; Abdollahifar, A ; Mahmoodi Hashemi, M ; Zirak, M ; Sharif University of Technology
2006
Abstract
At room temperature, zirconium oxychloride (ZrOCl2· 8H2O) efficiently catalyzes the direct Mannich-type reaction of a variety of in situ generated aldimines using aldehydes and anilines with ketones in a three-component reaction under solvent-free conditions. The reaction proceeds rapidly and affords the corresponding β-amino ketones in good to high yields with good to excellent stereoselectivities. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency. © Wiley-VCH Verlag GmbH & Co. KGaA, 2006
LiClO4 • 3H2O promoted highly regioselective ring-opening of epoxides with thiols under neutral conditions
, Article Catalysis Communications ; Volume 7, Issue 4 , 2006 , Pages 224-227 ; 15667367 (ISSN) ; Saidi, M. R ; Sharif University of Technology
2006
Abstract
A simple, rapid, atom economy and highly efficient procedure has been developed for thiolysis of epoxides by aromatic and aliphatic thiols under solvent-free conditions. A high regioselectivity in favor of nucleophilic attack at the benzylic carbon atom of aromatic epoxides, such as styrene oxide, is observed. However, aliphatic unsymmetrical alkenyl oxides undergo selective nucleophilic attack at the sterically less hindered carbon atom. A variety of β-hydroxy sulfides were obtained in short reaction time and excellent yields with nearly complete regioselectivity. © 2005 Elsevier B.V. All rights reserved
Solvent-free efficient synthesis of symmetrical isocyanurates by a combination catalyst: Sodium saccharin and tetrabutylammonium iodide
, Article Monatshefte fur Chemie ; Volume 135, Issue 7 , 2004 , Pages 849-851 ; 00269247 (ISSN) ; Koozehgiri, G. R ; Dekamin, M. G ; Sharif University of Technology
2004
Abstract
Combination of sodium saccharin and tetrabutylammonium iodide as a novel anionic catalyst system promotes selectively the trimerization of isocyanates to give symmetrical isocyanurates under solvent-free conditions. © Springer-Verlag 2004
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
Aza Michael Addition of Amines to α,β-Unsaturated Compounds and Alkene Epoxidation
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor)
Abstract
This thesis contains two parts .In the first part a catalyst such as AlCl3/Al20 has been demonstrated to catalyze Michael addition reaction of amines to a,�- unsaturated compounds with high yields , short reaction time and under solvent-free condition.The Michael addition to a,�- unsaturated compounds produces quantitively the mono addition products.The next part is about olefins epoxidation . Alkene epoxidation is a useful reaction in organic synthesis. Epoxides play an important role in industrial intermediates for the production of fine chemicals as well as pharmaceuticals .The hydrogen peroxide has been used as an oxidant because it is considered as an economical and appropriate reagent...
Solvent-free synthesis of 3-benzylpyrano[3,2-c]pyran/chromene-2,5-diones via tandem reaction of 4-hydroxy-6-methyl-pyran-2-one and 4-hydroxycoumarin with Baylis-Hillman adduct acetates
, Article Scientia Iranica ; Vol. 21, issue. 3 , 2014 , p. 735-741 ; 1026-3098 ; 2345-3605 ; Koushki Foroushani, B ; Lotfi Kalahroodi, E ; Sharif University of Technology
Abstract
4-hydroxycoumarin 2a and 4-hydroxy-6-methyl-pyran-2-one 2b were applied in a one-pot reaction with Baylis-Hillman adduct acetates 1 to form novel 3-benzylpyrano [3, 2-c] pyran-2, 5-diones 3 in high yields (70-85%). The synthesized framework is available in many biologically active moieties. The reaction was carried out under different conditions to achieve optimum conditions. The results indicated that Et3N, as a base under solvent-free conditions, was optimum. The reaction procedure and purification method are mild and straightforward
A simple approach to the synthesis of 3-substituted rhodanines and thiazolidine-2,4-diones
, Article Scientia Iranica ; Volume 20, Issue 6 , 2013 , Pages 1833-1838 ; 10263098 (ISSN) ; Shokri, A ; Saidi, M. R ; Sharif University of Technology
Sharif University of Technology
2013
Abstract
A novel synthesis of 3-substituted rhodanine and thiazolidine-2,4-dione derivatives, starting from aliphatic primary amines, carbon disulfide, and methyl 2-bromoacetate, is described. The reaction proceeds successfully both in water and under solvent-free conditions, but 2-thioxothiazolidin-4-one (rhodanine) derivatives were obtained under solvent free-conditions, and thiazolidine-2,4-dions were formed when water was used as the solvent
Commercial zinc oxide: a facile, efficient, and eco-friendly catalyst for the one-pot three-component synthesis of multisubstituted 2-aminothiophenes via the Gewald reaction
, Article Industrial and Engineering Chemistry Research ; Volume 51, Issue 44 , October , 2012 , Pages 14577-14582 ; 08885885 (ISSN) ; Ahmadi, S. J ; Rezaei Seresht, E ; Javadi, F ; Yasemi, M. A ; Hosseinpour, M ; Maleki, B ; Sharif University of Technology
2012
Abstract
An eco-friendly, simple, and effective protocol is developed for the synthesis of various multisubstituted 2-aminothiophenes. In the presence of a catalytic amount of ZnO (5 mol), ketones or aldehydes, malononitrile and elemental sulfur were converted to the corresponding 2-aminothiophene derivatives in moderate to high yields (27%-70%) under solvent-free conditions at 100 °C. Zinc oxide as an efficient, readily available, and reusable catalyst, showed very good catalytic activity for the synthesis of 2-aminothiophene derivatives. Thus far, little research has been reported on the Gewald reaction under solvent-free conditions; to the best of our knowledge, this is the first time that it has...
Oxazine containing molybdenum(VI)–oxodiperoxo complex immobilized on SBA-15 as highly active and selective catalyst in the oxidation of alkenes to epoxides under solvent-free conditions
, Article Microporous and Mesoporous Materials ; Volume 251 , 2017 , Pages 173-180 ; 13871811 (ISSN) ; Moradi Shoeili, Z ; Esmailpour, P ; Akbayrak, S ; Özkar, S ; Sharif University of Technology
Elsevier B.V
2017
Abstract
Molybdenum(VI)–oxodiperoxo complex containing an oxazine ligand, ([MoO(O2)2(phox)], phox: 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine) was conveniently synthesized and immobilized onto chloro-functionalized mesoporous silica SBA-15 by covalent bonding between the chloropropyl group on the internal surface of the pores and the nitrogen atom of oxazine ligand yielding [MoO(O2)2(phox)]/SBA-15. The resulting material was characterized by FT-IR, TGA, XRD, SEM, TEM, EDX, ICP-AES, BET and UV–vis spectroscopy. The heterogeneous catalyst [MoO(O2)2(phox)]/SBA-15 was employed in the epoxidation of alkenes, exhibiting high catalytic performance and selectivity for epoxide similar to that of homogeneous...
Ionic liquid-based ordered mesoporous organosilica-supported copper as a novel and efficient nanocatalyst for the one-pot synthesis of Biginelli products
, Article Microporous and Mesoporous Materials ; Volume 204, Issue C , 2015 , Pages 269-275 ; 13871811 (ISSN) ; Hosseinpoor, F ; Karimi, B ; Hajati, S ; Sharif University of Technology
Abstract
The preparation, characterization and catalytic application of a novel copper-loaded ionic liquid-based periodic mesoporous organosilica (Cu@PMO-IL) are described. The mesoporous structure of the Cu@PMO-IL material is characterized by transmission electron microscopy (TEM) and nitrogen adsorption-desorption analysis. The thermal stability of the material is also determined by thermal gravimetric analysis (TGA). The presence of copper species in the material framework is confirmed by X-ray photoelectron spectroscopy (XPS) and elemental analysis (EA). The catalytic application of Cu@PMO-IL nanocatalyst is then investigated in the Biginelli condensation of different aldehydes with urea and...
Microwave-assisted synthesis of 3-substituted coumarins using ZrOCl 2.8H2O as an effective catalyst
, Article Scientia Iranica ; Volume 16, Issue 1 C , 2009 , Pages 12-16 ; 10263098 (ISSN) ; Mirjafary, Z ; Saeidian, H ; Sharif University of Technology
2009
Abstract
An efficient route for the synthesis of 3-substituted coumarins via Knoevenagel condensation, using ZrOCl2.8H2O (10 mol %) as the. catalyst under microwave heating and solvent-free conditions, is described. This procedure offers several advantages, including the low loading of catalysts, high yields, clean reactions, short reaction times and the. use of various substrates, which make it a useful and attractive strategy for the. synthesis of 3-substituted coumarins. © Sharif University of Technology, June 2009
Highly efficient one-pot three-component mannich reaction under solvent-free conditions
, Article Scientia Iranica ; Volume 16, Issue 2 C , 2009 , Pages 94-98 ; 10263098 (ISSN) ; Ebrahimi, F ; Saidi, M. R ; Sharif University of Technology
2009
Abstract
A mild and practically-convenient one-pot procedure for the direct Mannich reaction has been developed using a condensation of amines, aldehydes and unmodified ketones under solvent free conditions in the presence of Znl 2 with good to excellent yields. The present methodology offers several advantages, such as excellent yields, simple procedures, short reaction times and milder conditions with very small amounts of catalyst. Furthermore, it is the first time that the catalytic activity of several catalysts under solvent free conditions has been studied. It was found that both the diastereoselectivity and the rate of reaction were improved with various Lewis acids and metal oxides. However,...