scholarly journals Molecular Sieve Supported Lanthanum Catalyst for the Efficient Synthesis of Polyhydroquinolines via Hantzsch Synthesis

2017 ◽  
Vol 61 (4) ◽  
pp. 278 ◽  
Author(s):  
Ágnes Magyar ◽  
Zoltán Hell

Molecular sieve supported lanthanum catalyst proved to be an efficient heterogeneous catalyst for the one-pot, four-component synthesis of polyhydroquinoline derivatives from aromatic aldehydes, dimedone, ethyl acetoacetate and ammonium acetate in ethanol via Hantzsch reaction. The method has several advantages such as simple reaction conditions, short reaction time, high yields and simple workup procedure, which make it an attractive route for the synthesis of polyhydroquinolines. The catalyst could be reused several times without the loss of its initial activity.

2005 ◽  
Vol 2005 (9) ◽  
pp. 600-602 ◽  
Author(s):  
Yu-Ling Li ◽  
Mei-Mei Zhang ◽  
Xiang-Shan Wang ◽  
Da-Qing Shi ◽  
Shu-Jiang Tu ◽  
...  

In this paper the preparation of 3,3,6,6-tetramethyl-9-aryl-1,2,3,4,5,6,7,8,9,10- decahydroacridin-1,8-dione derivatives from aromatic aldehydes, 5,5-dimethyl-1,3- cyclohexanedione and ammonium acetate in ionic liquids [bmim+][BF4-] is described. This new method has the advantages of easier work-up, milder reaction conditions, high yields and an environmentally benign procedure compared with other methods.


2014 ◽  
Vol 68 (8) ◽  
Author(s):  
Hamzeh Kiyani ◽  
Fatemeh Ghorbani

Abstract2-Amino-4-aryl-4H-benzo[h]chromenes and 3-amino-1-aryl-1H-benzo[f]chromenes were prepared by treating cyano-methylene compounds (malononitrile or ethyl cyanoacetate), substituted aromatic aldehydes, and naphtholic compounds in the presence of potassium phthalimide as a green, mild, efficient, and commercially available organocatalyst in aqueous media. The procedure was readily conducted and affords remarkable advantages such as safety, short reaction times, environmentally benign milder reaction conditions, no organic solvent required, and high yields.


2018 ◽  
Vol 15 (7) ◽  
pp. 982-988 ◽  
Author(s):  
Fahimeh S. Hosseini ◽  
Mohammad Bayat

Aim and Objectives: Development of simple synthetic routes for widely used organic compounds from readily available reagents is one of the major tasks in organic chemistry. Therefore, new approaches for increasing the molecular diversity of simple starting materials, are needed. Herein, an efficient synthesis of imidazo[1,2-a]pyridine, pyrido[1,2-a]pyrimidine and pyrido[1,2-a][1,3]diazepine derivatives is described. Materials and Methods: A one-pot, multi-component reaction of nitro ketene aminal derived from the addition of various 1,n-diamines to 1,1-bis(methylthio)-2-nitroethene with cyanoacetamide and aromatic aldehydes is described. The reactions are completed within 2-5 h, in ethanol at reflux, in good to high yields (70-93%). The structures of products were deduced from their IR, mass, 1H NMR, and 13C NMR spectra. Results: Optimal reaction conditions for the synthesis of products were obtained, when ethanol was used as the solvent at reflux. This protocol involves Michael reaction, imine–enamine tautomerization, and cyclization sequences. Conclusion: This work represents an efficient synthesis of imidazo[1,2-a]pyridine, pyrido[1,2-a]pyrimidine and pyrido[1,2-a][1,3]diazepine derivatives via a one-pot, multi-component reaction. The advantages of this protocol are mild conditions, easy accessibility of reactants, absence of catalyst, high atom economy, simple work-up and purification process with no chromatographic technique.


2017 ◽  
Vol 56 (4) ◽  
Author(s):  
Abdolkarim Zare ◽  
Roghayyeh Khanivar ◽  
Marzieh Hatami ◽  
Mohammad Mokhlesi ◽  
Mohammad Ali Zolfigol ◽  
...  

An efficient and simple solvent-free procedure for the synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[<em>a</em>]-xanthen-11-one derivatives <em>via</em> the one-pot multi-component condensation of dimedone with aromatic aldehydes and β-naphthol in the presence of protic acidic ionic liquid pyrazinium di(hydrogen sulfate) {Py(HSO<sub>4</sub>)<sub>2</sub>} as a green and homogeneous catalyst is described. All reactions proceed efficiently, and the title compounds are produced in high yields and in short reaction times.


2009 ◽  
Vol 7 (3) ◽  
pp. 550-554 ◽  
Author(s):  
Lakshman Gadekar ◽  
Shivshankar Mane ◽  
Santosh Katkar ◽  
Balasaheb Arbad ◽  
Machhindra Lande

AbstractNatural scolecite has been found as an effective catalyst for the one-pot synthesis of 2,4,5-triarylimidazole derivatives via a three component reaction using benzil or benzoin, aldehydes and ammonium acetate. This method provides several advantages such as being environmentally benign, reusable, possessing high yields with increased variations of the substituents in the product and preparative simplicity.


Synlett ◽  
2018 ◽  
Vol 30 (01) ◽  
pp. 89-93 ◽  
Author(s):  
Zoltán Hell ◽  
Ágnes Magyar

A series of 2,4,5-trisubstituted-imidazoles has been synthesized with good to excellent yields by the one-pot condensation reaction of 1,2-dicarbonyl compounds, benzaldehydes, and ammonium acetate in the presence of 4 Å molecular sieves modified with titanium(IV) as an efficient heterogeneous catalyst. The catalyst could be recovered easily and reused without significant loss of activity.


2014 ◽  
Vol 79 (4) ◽  
pp. 401-409 ◽  
Author(s):  
Ali Kiasat ◽  
Simin Nazari ◽  
Jamal Davarpanah

An efficient synthesis of 1,4-dihydropyridine & polyhydroquinolien derivatives using b-Cyclodextrin-polyurethane polymer (?-CDPU) as a stationary microvessel and neutral heterogeneous catalyst via a four component coupling of aldehydes, ?-ketoester (2 mol) and ammonium acetate under solvent-free conditions is described. Compared with the classical Hantzsch reaction, this new method has the advantages of good yield, short reaction time and methodological simplicity. ?-CDPU was proved to be an efficient heterogeneous catalyst which could be easily handled and removed from the reaction mixture by simple filtration, and also recovered and reused without loss of reactivity.


RSC Advances ◽  
2018 ◽  
Vol 8 (40) ◽  
pp. 22498-22505 ◽  
Author(s):  
Jing Sun ◽  
Yu Zhang ◽  
Chao-Guo Yan

The one-pot four-component reaction of aromatic aldehydes, malononitrile, 1,3-thiazolidinedione and ethyl glycinate hydrochloride in ethanol in the presence of triethylamine afforded trans-dihydrothiophene.


2013 ◽  
Vol 68 (4) ◽  
pp. 362-366 ◽  
Author(s):  
Shahrzad Abdolmohammadi ◽  
Mahdieh Mohammadnejad ◽  
Faezeh Shafaei

A series of tetrahydrobenzo[c]acridinone derivatives have been prepared by a one-pot fourcomponent reaction of 1-naphthol, aromatic aldehydes, dimedone, and ammonium acetate in aqueous media using a catalytic amount of titanium dioxide nanoparticles (TiO2 NPs). The advantages of this novel protocol include the excellent yields, operational simplicity, short reaction time, easy work-up, reusability of the catalyst and an environmentally friendly procedure.


2011 ◽  
Vol 76 (4) ◽  
pp. 235-241 ◽  
Author(s):  
Li-Qiang Wu ◽  
Wei-Lin Li ◽  
Fu-Lin Yan

A series of new 8-aryl-7,8-dihydro[1,3]dioxolo[4,5-g]chromen-6-ones were synthesized via a three-component reaction of 3,4-methylenedioxyphenol, aromatic aldehydes and Meldrum’s acid in the presence of CeCl3·7H2O under solvent-free conditions. The method provided several advantages such as easy work-up, high yields and environmentally benign procedure.


Sign in / Sign up

Export Citation Format

Share Document