Green multicomponent synthesis of four different classes of six-membered N-containing and O-containing heterocycles catalyzed by an efficient chitosan-based magnetic bionanocomposite

2018 ◽  
Vol 90 (2) ◽  
pp. 387-394 ◽  
Author(s):  
Ali Maleki ◽  
Mina Ghassemi ◽  
Razieh Firouzi-Haji

Abstract In this work, an efficient chitosan-based magnetic bionanocomposite was synthesized via a two-step method and characterized by Fourier-transform infrared (FT-IR) spectroscopy, thermo gravimetric analysis (TGA), energy-dispersive X-ray (EDX) analysis and scanning electron microscopy (SEM) images. Then, it was used as a heterogeneous catalyst for the one-pot multicomponent syntheses of a variety of heterocyclic compounds including 2-amino-4H-pyrans, 2-amino-4H-chromens and polyhydroquinoline derivatives in ethanol at room temperature. The catalyst was simply separated from the reaction mixture by an external magnet and reused several times. The products were isolated from the reaction mixtures, without any need of column chromatography, in high-to-excellent yields. A reusable and easily recoverable catalyst, use of a green solvent, room temperature and mild reaction conditions are some advantages of the present work.

SynOpen ◽  
2021 ◽  
Author(s):  
Mina Ghassemi ◽  
Ali Maleki

Copper ferrite (CuFe2O4) magnetic nanoparticles (MNPs) were synthesized via thermal decomposition method and applied as a reusable and green catalyst in the synthesis of functionalized 4H-pyran derivatives using malononitrile, an aromatic aldehyde and a β-ketoester in ethanol at room temperature. Then it was characterized by Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX) analysis, scanning electron microscopy (SEM) images, thermo gravimetric and differential thermo gravimetric (TGA/DTG) analysis. The catalyst was recovered from the reaction mixture by applying an external magnet and decanting the mixture. Recycled catalyst was reused for several times without significant loss in its activity. Running the one-pot three-component reaction at room temperature, no use of eternal energy source and using a green solvent provide benign, mild, and environmentally friendly reaction conditions; as well, ease of catalyst recovering, catalyst recyclability, no use of column chromatography and good to excellent yields are extra advantages of this work.


2021 ◽  
Vol 18 ◽  
Author(s):  
Yatin U. Gadkari ◽  
Rajesh D. Shanbhag ◽  
Vikas N. Telvekar

: An efficient methodology for the synthesis of 1,3-thiazolidin-4-ones using L-Proline as catalyst under aqueous conditions has been developed. The one-pot, multicomponent reaction of aromatic/heterocyclic aldehyde, aromatic amine and thioglycolic acid at room temperature give 1,3-thiazolidin-4-ones in moderate to good yields. Further, the current approach is notably greener than traditional methods with E-factor of 3.1 and the eco scale score of 96. The developed protocol offers several features, such as being simple, environmentally benign, energy-efficient, economical, mild conditions, shorter reaction time.


2021 ◽  
Vol 6 (2) ◽  
pp. 111-115
Author(s):  
H.P. Parekh ◽  
M.H. Chauhan ◽  
N.L. Solanki ◽  
V.H. Shah

In present work, a series of novel [1,2,4]triazolo[1,5-a]quinoline derivatives (HP-101-110) have been synthesized using multi-component reaction at room temperature in the presence of ammonium chloride as mild, cost effective green catalyst along with water as eco-friendly green solvent. The synthesis of 1,2,4-triazolo[1,5-a]quinolines (HP-101-110) was achieved by two step process. In first step, diversified Hantzsch pyridine reaction of an appropriate aromatic aldehyde, malononitrile, dimedone and benz hydrazide using ethanol as a solvent gives N-(2-amino-3-cyano-7,7-dimethyl-5-oxo-4-phenyl-5,6,7,8- tetrahydro-quinolin-1(4H)-yl)-4-hydroxybenzamide derivatives. In the second step, synthesis of the final product 2-(4-hydroxyphenyl)-8,8-dimethyl-6-oxo-5-phenyl-6,7,8,9-tetrahydro[1,2,4]triazolo[1,5- a]-quinoline-4-carbonitriles was achieved by the intramolecular cyclization of step 1 product.The structure of all the synthesized compounds (HP101-110) has been elucidated by FT-IR, 1H & 13C NMR, mass spectral data and elemental analyses.


2022 ◽  
Vol 16 ◽  
Author(s):  
Mustapha Dib ◽  
Marieme Kacem ◽  
Soumaya Talbi ◽  
Hajiba Ouchetto ◽  
Khadija Ouchetto ◽  
...  

Background: Pyran is an heterocyclic oxygen-containing compound that displays a wide range of therapeutic activities. Additionally, pyran is also one of the important structural subunits widely found in pharmaceuticals products. This makes it a recent focus for researchers from the industry and academic institutions. Herein, we reported an efficient and environmentally friendly one-pot strategy for the synthesis of bioactive 4H-pyran compounds via a multicomponent reaction of ethyl acetoacetate, malononitrile and substituted aromatic aldehydes in the presence of the heterogeneous spinel catalyst ( MgAl2O4 ) under mild conditions (room temperature and green solvents). The MgAl2O4 nanocatalyst was prepared from Mg/Al-LDH with a molar ratio 3 of Mg2+/Al3+ by heat treatment at 800°C. The samples were studied by a various characterization techniques such as XRD, TG-dTG, FT-IR and N2 adsorption-desorption. Good to excellent yields and facile separation of the catalyst from the reaction mixture are two of the most appealing features of this approach. Thus, bioactive molecules with pyran units may have fascinating biological properties. An efficient and green strategy for the one-pot synthesis of bioactive 4H-pyran compounds has been described. The pyrans heterocycles were produced by multicomponent reaction of ethyl acetoacetate, malononirile and substituted aromatic aldehydes in the presence of MgAl2O4 spinel nanocatalyst under mild conditions (room temperature and green solvents). MgAl2O4 nanocatalytst was prepared from Mg/Al-LDH with a molar ratio 3 of Mg2+/Al3+ by thermal treatment at 800°C. The samples were investigated by various characterization techniques such as XRD, TG-dTG, FT-IR and N2 adsorption-desorption. The following are the appealing qualities of this unique strategy including good to exceptional yields, and ease of separation of catalyst from the reaction mixture. Thus, the obtained bioactive compounds containing pyrans motif can be exhibiting interested biological activities. Methods: The substituted 4H-pyran compounds were carried out by condensation reaction of substituted aromatic aldehydes, ethyl ethyl acetoacetate and malononirile by using MgAl2O4 nanocatalyst under sustainable conditions. Objective: To develop an efficient methodology for synthesis of 4H-pyran heterocyclic molecules may have interesting applications in biology using a heterogeneous and easily synthesized catalyst. Results: This procedure outlines the synthesis of bioactive compounds in good yields and with ease of catalyst extraction from the reaction mixture under sustainable reaction conditions. Conclusion: In conclusion, it is important to reiterate that a spinel nanostucture has been successfully prepared and fully characterized using different physicochemical analysis methods. The catalytic activity of this heterogeneous catalyst was examined through the one-pot condensation of aryl benzaldehyde, malononitrile and ethyl acetoacetate. Therefore, we have developed a green method for the preparation of 4H-pyrans derivatives using MgAl2O4 as an efficient heterogeneous catalyst. The reactions were performed under green conditions, which have many benefits such as undergoing a simple procedure, good to excellent yields and easy to separate the catalyst.


2018 ◽  
Author(s):  
Huong T. D. Nguyen ◽  
Y B. N. Tran ◽  
Hung N. Nguyen ◽  
Tranh C. Nguyen ◽  
Felipe Gándara ◽  
...  

<p>Three novel lanthanide metal˗organic frameworks (Ln-MOFs), namely MOF-590, -591, and -592 were constructed from a naphthalene diimide tetracarboxylic acid. Gas adsorption measurements of MOF-591 and -592 revealed good adsorption of CO<sub>2</sub> (low pressure, at room temperature) and moderate CO<sub>2</sub> selectivity over N<sub>2</sub> and CH<sub>4</sub>. Accordingly, breakthrough measurements were performed on a representative MOF-592, in which the separation of CO<sub>2</sub> from binary mixture containing N<sub>2</sub> and CO<sub>2</sub> was demonstrated without any loss in performance over three consecutive cycles. Moreover, MOF-590, MOF-591, and MOF-592 exhibited catalytic activity in the one-pot synthesis of styrene carbonate from styrene and CO<sub>2</sub> under mild conditions (1 atm CO<sub>2</sub>, 80 °C, and solvent-free). Among the new materials, MOF-590 revealed a remarkable efficiency with exceptional conversion (96%), selectivity (95%), and yield (91%). </p><br>


2020 ◽  
Vol 24 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Zita Rádai ◽  
Réka Szabó ◽  
Áron Szigetvári ◽  
Nóra Zsuzsa Kiss ◽  
Zoltán Mucsi ◽  
...  

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.


2020 ◽  
Vol 17 ◽  
Author(s):  
Saeid Azimi ◽  
Niloofar Mohamadighader

Abstract: A new solid catalyst was synthesized from an ionic liquid and heterogenised by changing anion reaction. The new heterogeneous acidic catalyst was characterized by SEM images, EDS analysis, AFM images, Ft-IR, HNMR, 13CNMR and Mass Spectroscopy. It was applied to synthesis of tri-arylmethanes throughout one-pot tri-component reactions among aromatic aldehydes, N,N-dimethylaniline and other carbonic nucleophiles such as anisole and indole. Hence, synthesis of convenient and inexpensive micro-heterogeneous catalyst was introduced, the efficiency of which was confirmed. Also, various useful products were synthesized throughout this simple and clean procedure.


Chemistry ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 783-799
Author(s):  
Maryam Ariannezhad ◽  
Davood Habibi ◽  
Somayyeh Heydari ◽  
Vahideh Khorramabadi

A new magnetic supported manganese-based coordination complex (Fe3O4@SiO2@CPTMS@MBOL@ Mn) was prepared in consecutive stages and characterized via various techniques (VSM, SEM, TEM, XRD, FT-IR, EDX, TG-DTA, and ICP). To evaluate its application, it was used for synthesis of divers Indazolophthalazinetriones in a simple procedure via the one-pot three-component condensation reaction of aldehydes, dimedone, and phthalhydrazide in ethanol under reflux conditions. The Mn catalyst can be recycled without any noticeable loss in catalytic activity. Additionally, the antibacterial properties of the nano-catalyst were studied against some bacterial strains.


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