نتایج جستجو برای: Trisubstituted imidazoles

تعداد نتایج: 4534  

Journal: :Organic letters 2004
Scott E Wolkenberg David D Wisnoski William H Leister Yi Wang Zhijian Zhao Craig W Lindsley

[reaction: see text] A simple, high-yielding synthesis of 2,4,5-trisubstituted imidazoles from 1,2-diketones and aldehydes in the presence of NH(4)OAc is described. Under microwave irradiation, alkyl-, aryl-, and heteroaryl-substituted imidazoles are formed in yields ranging from 80 to 99%. Short syntheses of lepidiline B and trifenagrel illustrate the utility of this approach.

Journal: :Green and Sustainable Chemistry 2023

Substituted imidazoles are of interest because their useful biological activities. While several methods have been developed for the synthesis such compounds, some reported utilize corrosive or toxic catalysts. We report a bismuth (III) triflate catalyzed multicomponent 2,4,5-trisubstituted imidazoles. Bismuth compounds attractive from green chemistry perspective they remarkably non-toxic and n...

Journal: :journal of nanostructures 2012
a. bamoniri s. rohani

a general synthetic route to the synthesis of imidazoles has been developed using nano sbcl5/sio2 under solvent-free conditions. the multi-component reactions of aldehydes, benzil and ammonium acetate were carried out to afford some trisubstituted imidazole derivatives. this method provides several advantages like simple work-up, environmentally benign, and shorter reaction times along with hig...

A. Bamoniri, S. Rohani

A general synthetic route to the synthesis of imidazoles has been developed using nano SbCl5/SiO2 under solvent-free conditions. The multi-component reactions of aldehydes, benzil and ammonium acetate were carried out to afford some trisubstituted imidazole derivatives. This method provides several advantages like simple work-up, environmentally benign, and shorter reaction times along wi...

Journal: :Acta poloniae pharmaceutica 2009
Asif Husain Sushma Drabu Nitin Kumar

Disubstituted imidazoles were prepared by reacting appropriate phenylglyoxal with different aryl aldehydes in the presence of ammonium acetate. Trisubstituted imidazoles were prepared by reacting disubstituted imidazoles with chlorobenzene in the presence of catalytic amount of triethylamine (TEA). The synthesized compounds were characterized on the basis of IR, 1H-NMR and mass spectral data an...

Journal: :journal of particle science and technology 0
zinat gordi department of chemistry, payame noor university, tehran, iran. mohammad vazan department of chemistry, payame noor university, tehran, iran.

a series of tri- and tetra- substituted imidazoles were synthesized from benzyl, aldehyde and ammonium acetate in the presence of zeolite as an ecofriendly reusable catalyst under microwave irradiation in the absence of solvent. the yields are high to excellent and the use of microwave irradiation reduces reaction times to few minute.

Javad Safari, Simin Naseh Zahra Akbari Zohre Zarnegar

A simple highly versatile and efficient sonochemical synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles is achieved by condensation of 1,2-dicarbonyl compound, aldehyde, ammonium acetate and primary amine using antimony trichloride immobilized on silica gel (SiO2-OSbCl2) as a catalyst in ethanol at moderate temperature. Operational simplicity, practicability and applicabi...

Javad Safari, Simin Naseh Zahra Akbari Zohre Zarnegar

A simple highly versatile and efficient sonochemical synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles is achieved by condensation of 1,2-dicarbonyl compound, aldehyde, ammonium acetate and primary amine using antimony trichloride immobilized on silica gel (SiO2-OSbCl2) as a catalyst in ethanol at moderate temperature. Operational simplicity, practicability and applicabi...

Journal: :iranian journal of catalysis 2014
javad safari zohre zarnegar simin naseh zahra akbari

a simple highly versatile and efficient sonochemical synthesis of 1,2,4,5-tetrasubstituted and 2,4,5-trisubstituted imidazoles is achieved by condensation of 1,2-dicarbonyl compound, aldehyde, ammonium acetate and primary amine using antimony trichloride immobilized on silica gel (sio2-osbcl2) as a catalyst in ethanol at moderate temperature. operational simplicity, practicability and applicabi...

Journal: :organic chemistry research 2016
seyyed jafar saghanezhad alireza kiasat

one-pot preparation of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles has been conducted in the presence of poly(4-vinylpyridinium butane sulfonic acid) hydrogen sulfate, p(4vpbsa)hso4, as an efficient dual acidic catalyst under solvent-free conditions. reusability of the catalyst, easy work-up procedure, eco-friendly reaction conditions, short reaction times and high yields of th...

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