13269-91-5Relevant articles and documents
Experimental and computational study of metal-free Br?nsted acidic ionic liquid catalyzed benzylic C(sp3)–H bond activation and C–N, C–C cross couplings
Valiyev, Isa,Abdullayev, Yusif,Yagubova, Sevinj,Baybekov, Shamkhal,Salmanov, Cavanshir,Autschbach, Jochen
, p. 410 - 419 (2019)
Metal and solvent free synthesis of tetrasubstituted imidazoles and tetrasubstituted pyrazines from 1,2-diketones and aliphatic amines is studied experimentally and computationally. Various ionic liquids (ILs) are taken as a catalyst in 10 mol% for the re
One-pot synthesis of tetra-substituted imidazoles on silica gel under microwave irradiation
Xu, Yu,Liu, Yan-Zhi,Rui, Lei,Liu, Lei,Guo, Qing-Xiang
, p. 87 - 93 (2004)
A new procedure for synthesis of tetra-substituted imidazoles was developed. A series of imidazole derivatives including six new compounds were synthesized by this procedure via condensation of benzoin, aromatic aldehyde, amine and ammonium acetate in the presence of silica gel under solvent-free microwave irradiation.
A novel one-pot synthesis of tetrasubstituted imidazoles under solvent-free conditions and microwave irradiation
Balalaie, Saeed,Hashemi, Mohammed M.,Akhbari, Maryam
, p. 1709 - 1711 (2003)
The one-pot, three-component condensation of benzil, benzonitrile derivatives and primary amines on the surface of silica gel under solvent-free conditions and microwave irradiation provided tetrasubstituted imidazoles in high yields.
Increased SBA-15-SO3H catalytic activity through hydrophilic/hydrophobic fluoroalkyl-chained alcohols (RFOH/SBA-15-Pr-SO3H)
Rostamnia, Sadegh,Doustkhah, Esmail
, p. 1345 - 1347 (2015)
A superior catalytic activity for the SBA-15-functionalized sulfonic acid containing fluoroalkyl chain alcohols (RFOH/SBA-15-Pr-SO3H adduct) is presented for the synthesis of highly substituted imidazoles. The advantages of this method include low catalyst loading, simple procedure, excellent yields, recyclability of catalyst, and short reaction times.
Silica coated magnetic NiFe2O4 nanoparticle supported phosphomolybdic acid; Synthesis, preparation and its application as a heterogeneous and recyclable catalyst for the one-pot synthesis of tri- and tetra-substituted imidazoles under solvent free conditions
Maleki, Behrooz,Eshghi, Hossein,Khojastehnezhad, Amir,Tayebee, Reza,Ashrafi, Samaneh Sedigh,Kahoo, Golnoosh Esmailian,Moeinpour, Farid
, p. 64850 - 64857 (2015)
In this research, a magnetically-recoverable catalyst (NiFe2O4@SiO2-H3PMo12O40) was prepared by supporting phosphomolybdic acid (H3PMo12O40) onto silica-coated NiFe2O4 nanoparticles. The prepared sample was characterized by FT-IR, TEM, SEM and VSM techniques and then the catalytic activity of this catalyst was investigated in the synthesis of tri- and tetra-substituted imidazole derivatives. More importantly, the catalyst was easily isolated from the reaction mixture by a magnetic bar and reused at least ten times without significant degradation in its activity.
BF3·SiO2: an efficient reagent system for the one-pot synthesis of 1,2,4,5-tetrasubstituted imidazoles
Sadeghi, Bahareh,Mirjalili, Bi Bi Fatemeh,Hashemi, Mohammad M.
, p. 2575 - 2577 (2008)
Silica-supported boron trifluoride (BF3·SiO2) is an efficient, readily available and reusable catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles using benzil, an aromatic aldehyde and an amine in the presence of ammonium acetate. This one-pot procedure is very simple, affording good to excellent yields.
Elemental Sulfur-Promoted Aerobic Cyclization of Ketones and Aliphatic Amines for Synthesis of Tetrasubstituted Imidazoles
Chen, Xiangui,Wang, Zhen,Huang, Huawen,Deng, Guo-Jun
, p. 4017 - 4022 (2018)
Elemental sulfur-promoted cyclization for the one-pot synthesis of tetra-substituted imidazoles from benzylamines and ketones is described. Elemental sulfur combined with molecular oxygen as the benign co-oxidant was found to be the key for the high efficiency of this transformation under metal-free conditions. A range of tetrasubstituted imidazoles were synthesized from simple ketones and amines with good functional group tolerance. (Figure presented.).
Efficient room-temperature synthesis of tri- and tetrasubstituted imidazoles catalyzed by ZrCl4
Sharma,Jyothi,Lakshmi, P. Sree
, p. 2991 - 3000 (2006)
A general protocol has been developed for the rapid synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles in high yields using ZrCl4 as an efficient catalyst at room temperature. A variety of aromatic, aliphatic, and terpenoidal aldehydes underwent condensation with NH4OAc/amines to give the imidazoles. Similarly, the imidazole glycoconjugates are prepared in good yields from the corresponding glycosyl aldehydes. Copyright Taylor & Francis Group, LLC.
Facile synthesis of imidazoles by an efficient and eco-friendly heterogeneous catalytic system constructed of Fe3O4 and Cu2O nanoparticles, and guarana as a natural basis
Varzi, Zahra,Esmaeili, Mir Saeed,Taheri-Ledari, Reza,Maleki, Ali
, (2021)
In this study, an efficient hybrid nanocatalyst made of guar gum (guarana, as a natural basis), magnetic iron oxide nanoparticles, and copper(I) oxide nanoparticles (Cu2O NPs) is fabricated and suitably applied for catalyzing the multicomponent (three- and four-component) synthesis reactions of imidazole derivatives. Here, an easy preparation strategy for this novel catalytic system (Cu2O/Fe3O4@guarana) is presented. Then, the application of this catalytic system for the synthesis of imidazole derivatives is precisely investigated. For this purpose, ultrasonication is introduced as an efficient and fast method. In summary, the high catalytic efficiency of Cu2O/Fe3O4@guarana nanocomposite is well demonstrated by high reaction yields obtained in the presence of a small amount of this nanocomposite, under mild conditions. Wide active surface area, substantial magnetic behavior, excellent heterogeneity, suitable stability, well reusability, and etc. have distinguished this catalytic system as an instrumental tool for facilitating the complex synthetic reactions.
Four-component, one-pot synthesis of tetra-substituted imidazoles using a catalytic amount of MCM-41 or p-TsOH
Shoar, Rahim Hekmat,Rahimzadeh, Golnaz,Derikvand, Fatemeh,Farzaneh, Maryam
, p. 1270 - 1275 (2010)
An improved and rapid one-pot synthesis of tetrasubstituted imidazoles by condensing benzil, ammonium acetate, amines, and aromatic aldehydes and using a catalytic amount of silica structure MCM-41 or p-toluenesulfonic acid (p-TsOH) as efficient, green, reusable catalysts in excellent yields is reported.
Cu(II) immobilized on guanidinated epibromohydrin-functionalized γ-Fe2O3@TiO2 (γ-Fe2O3@TiO2-EG-Cu(II)): A highly efficient magnetically separable heterogeneous nanocatalyst for one-pot synthesis of highly substituted imidazoles
Nejatianfar, Mahdi,Akhlaghinia, Batool,Jahanshahi, Roya
, (2018)
A simple, efficient and eco-friendly procedure has been developed using Cu(II) immobilized on guanidinated epibromohydrin-functionalized γ-Fe2O3@TiO2 (γ-Fe2O3@TiO2-EG-Cu(II)) for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles, via the condensation reactions of various aldehydes with benzil and ammonium acetate or ammonium acetate and amines, under solvent-free conditions. High-resolution transmission electron microscopy analysis of this catalyst clearly affirmed the formation of a γ-Fe2O3 core and a TiO2 shell, with mean sizes of about 10–20 and 5–10?nm, respectively. These data were in very good agreement with X-ray crystallographic measurements (13 and 7?nm). Moreover, magnetization measurements revealed that both γ-Fe2O3@TiO2 and γ-Fe2O3@TiO2-EG-Cu(II) had superparamagnetic behaviour with saturation magnetization of 23.79 and 22.12?emu g?1, respectively. γ-Fe2O3@TiO2-EG-Cu(II) was found to be a green and highly efficient nanocatalyst, which could be easily handled, recovered and reused several times without significant loss of its activity. The scope of the presented methodology is quite broad; a variety of aldehydes as well as amines have been shown to be viable substrates. A mechanism for the cyclocondensation reaction has also been proposed.
One-pot Synthesis of Polysubstituted Imidazoles Catalyzed by an Ionic liquid
Maleki, Behrooz,Kahoo, Golnoosh Esmailian,Tayebee, Reza
, p. 461 - 472 (2015)
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Catalytic activity of Mg-Al hydrotalcites and derived mixed oxides for imination reactionsviaan oxidative-dehydrogenation mechanism
Vala, Naresh,Joshi, Pradyuman A.,Mishra, Manish
supporting information, p. 8859 - 8868 (2020/06/08)
The catalytic activities of Mg-Al hydrotalcites and derived Mg-Al mixed oxides were studied for the imination of benzylic substrates (benzyl amine and benzyl alcohol), with aniline as a model reaction, to establish a green and cost-effective catalytic (precious metal free) process for imination and tandem reactions utilizing alcohols as reagents. The Mg-Al mixed oxide (Mg/Al ratio = 3.0) was found to be an efficient catalyst for imination reactions to synthesize cross-imines with high selectivity as well as for tandem reactions of alcohols. Basic sites of catalysts adsorb benzylic substrates through the hydrogen of their functional groups (-NH2/-OH) and activate (weaken) benzylic C-H bonds for hydride elimination. Thus, basic sites catalyze the reaction by activating benzylic substrates for oxidative-dehydrogenation (i.e., deprotonation followed by hydride elimination with the help of oxygen) to produce reactive imine/carbonyl intermediates, which undergo subsequent nucleophilic reactions with amine.
