scholarly journals An efficient green synthesis of polyfunctional pyrazole-triazole hybrids and bis-triazoles via chromium incorporated fluorapatite encapsulated iron oxide nanocatalyst

2021 ◽  
Vol 10 (4) ◽  
pp. 445-458 ◽  
Author(s):  
Iman Rezaei ◽  
Manouchehr Mamaghani

In this report, novel chromium incorporated fluorapatite encapsulated iron oxide (γ-Fe2O3@FAp@Cr) nanocatalyst was synthesized and characterized by FT-IR, TEM, SEM, XRD and EDX techniques. The catalyst was used in the synthesis of various derivatives of pyrazole-triazole hybrids via the reaction of thiosemicarbazide or semicarbaside and pyrazolecarbaldehydes at room temperature with excellent yields and short reaction times. The protocol was also used in the synthesis of bis-triazoles in high yield and reasonable reaction time. The nanocatalyst was comfortably separated from the reaction mixture by an external magnet and was reused in six consecutive cycles without any remarkable changes in its catalytic performance.

2021 ◽  
Vol 11 (3) ◽  
pp. 215
Author(s):  
Achraf El Hallaoui ◽  
Tourya Ghailane ◽  
Soukaina Chehab ◽  
Youssef Merroun ◽  
Rachida Ghailane ◽  
...  

<p>This work aims to prepare a new bimetallic phosphate catalyst using a new simple and effective method. This new catalyst was ready for the first time by a modification of Triple Super Phosphate (TSP) fertilizer with silver sulfate (AgSO<sub>4</sub>), followed by the impregnation of the aluminum atoms using aluminum nitrate (Al(NO<sub>3</sub>)<sub>3</sub>). The use of Al/Ag<sub>3</sub>PO<sub>4</sub>, for the first time as a heterogeneous catalyst in organic chemistry, offers a new, efficient, and green pathway for synthesizing 1,2-dihydro-l-phenyl-3H-naphth[1,2-e]-[1,3]oxazin-3-one derivatives by one-pot three-component cyclocondensation of b-naphthol, aryl aldehyde, and urea. The structure and the morphology of the prepared catalyst were characterized by spectroscopic methods such as X-Ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FT-IR), and dispersive X-ray spectrometry coupled with a scanning electron microscope (EDX-SEM). In addition, the optimization of the reaction parameters was carried out considering the effect of catalyst amount, the temperature, and the solvent. The procedure described herein allowed a comfortable preparation of oxazine derivatives with excellent yields, short reaction times, and in the absence of organic solvent.</p>


2020 ◽  
Vol 213 ◽  
pp. 01003
Author(s):  
Hui Li ◽  
Xi Cao ◽  
Huiting He ◽  
Jian Liu ◽  
Weijian Xiang ◽  
...  

A novel solid-acid catalyst (PVC-EDA-SO4H) based on polyvinyl chloride (PVC) were prepared after amination of Ethylenediamine (EDA) and anchorage of sulfuric acid. The as-prepared catalyst was characterized by FT-IR, Element analysis, Chemical titration and Thermal analysis, the results indicated that the sulfuric acid was successfully anchored on PVC. The PVC-EDA-SO4H showed excellent catalytic performance for the synthesis of bisphenol F, and achieved almost high yield and selectivity (94%) of BPF under the mind reaction conditions. Meanwhile, exhibited excellent reusability without the significant loss after six cycles via simple filtration.


2020 ◽  
Vol 17 (7) ◽  
pp. 517-522
Author(s):  
Azizollah Habibi ◽  
Sahar Khosravi ◽  
Seyyed M. Shahcheragh ◽  
Mohd B. Abdul Rahman

In the current study, a green, one-pot, three-component reaction was performed to prepare novel N-substituted 5-amino-1,3,4-thiadiazole derivatives. The thiadiazoles were obtained from the reaction of a ketene S,S-acetal of Meldrum’s acid or barbituric acid (as key intermediates), hydrazine, and isothiocyanate. The key advantages of this manner include environmentally safe reactions, high yield, appropriate reaction time, simple reaction conditions, and use of a green reaction solvent. The structure of thiadiazoles was determined based on the spectroscopic data.


Author(s):  
Hodhaifa Derdar ◽  
Mohammed Belbachir ◽  
Amine Harrane

A new green polymerization technique to synthesis polylimonene (PLM) is carried out in this work. This technique consists of using Maghnite-H+ as eco-catalyst to replace Friedel-Crafts catalysts which are toxics. Maghnite-H+ is a montmorillonite silicate sheet clay which is prepared through a simple exchange process. Polymerization experiments are performed in bulk and in solution using CH2Cl2 as solvent. Effect of reaction time, temperature and amount of catalyst is studied, in order to find the optimal reaction conditions. The polymerization in solution leads to the best yield (48.5%) at -5°C for a reaction time of 6 h but the bulk polymerization, that is performed at 25°C, remains preferred even if the yield is lower (40.3%) in order to respect the principles of a green chemistry which recommend syntheses under mild conditions, without solvents and at room temperature. The structure of the obtained polymer (PLM) is confirmed by FT-IR and Nuclear Magnetic Resonance of proton (1H-NMR). The glass transition temperature (Tg) of the polylimonene is defined using Differential Scanning Calorimetry (DSC) and is between 113°C and 116°C. The molecular weight of the obtained polymer is determined by Gel Permeation Chromatography (GPC) analysis and is about 1360 g/mol. Copyright © 2019 BCREC Group. All rights reservedReceived: 26th May 2018; Revised: 11st September 2018; Accepted: 22nd September 2018; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Derdar, H., Belbachir, M., Harrane, A. (2019). A Green Synthesis of Polylimonene Using Maghnite-H+, an Exchanged Montmorillonite Clay, as Eco-Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 69-78 (doi:10.9767/bcrec.14.1.2692.69-78)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.2692.69-78 


2021 ◽  
Vol 15 (4) ◽  
pp. 551-558
Author(s):  
Sarra Sabrina Aiche ◽  
◽  
Hodhaifa Derdar ◽  
Zakaria Cherifi ◽  
Mohammed Belbachir ◽  
...  

In the present work we have explored a new catalyst prepared with Algerian clay and a new method to synthesise polystyrene and poly(1,3-dioxolane). This technique consists of using Algerian modified clay (Kaolinite-H+) as a green catalyst. Kaolinite-H+ is a proton exchanged clay which is prepared through a simple exchange process. Synthesis experiments are performed in bulk. The polymerization of styrene in bulk leads to the yield of 83 % at room temperature with the reaction time of 3 h. Molecular weight of the obtained polystyrene is calculated by 1H NMR and is about 2196 g/mol. Polymerization of (1,3-dioxolane) is carried out at room temperature with the reaction time of 3 h and polymerization yield of 91 %. The calculated molecular weight of the obtained poly(1,3-dioxolane) is about 573 g/mol. The structure of the obtained polymers is confirmed by FT-IR and 1H NMR. The modified clay (Kaolinite-H+) is characterized by FT-IR, XRD and SEM analysis.


2020 ◽  
Vol 19 (05) ◽  
pp. 1950037
Author(s):  
Tao Yu ◽  
Hang Guo ◽  
Xiangyu Wang ◽  
Baojun Li ◽  
Xianji Guo

Using trirutile-structure layered tantalum–tungsten acid as the layered host, [Formula: see text]-propylamin as the pre-swelling agent and aqueous solution of [Fe3(CH3COO)7(OH)(H2O)]NO3 as the pillaring solution, oligomeric polyhydroxyacetato-Fe(III) species-intercalated layered HTaWO6 was synthesized by a stepwise ion-exchange way at room temperature. Upon calcining at 673[Formula: see text]K in air atmosphere, iron oxide-pillared layered HTaWO6with nanoscale interlayer distance (denoted as Fe2O3-HTaWO[Formula: see text] was obtained. A series of Fe2O3-HTaWO6 samples with various Fe contents were prepared by using different volume of Fe(III)-pillaring solution. The layered intermediates obtained at each stage of the ions-exchange process and the final layered products were characterized by powder XRD, FT-IR, DR UV-Vis and SEM techniques. The photocatalytic performance of the Fe2O3-pillared layered HTaWO6 samples for degradation of rhodamine B was investigated. Compared with un-pillared layered HTaWO6, the Fe2O3-pillared layered HTaWO6 exhibited a significantly-improved photo-absorption performance and an enhanced photocatalytic activity. The Fe2O3-HTaWO6 sample with 5.8% (wt) iron showed the best catalytic performance in the photodegradation reaction of rhodamine B.


2020 ◽  
Vol 17 (4) ◽  
pp. 304-312
Author(s):  
Leila Z. Fekri

Background: Imidazo[1,2-a]pyrimidinone, quinazolinone and amide derivatives have attracted a lot of interest because of their broad scope of biological and pharmacological activities. There are a lot of methods reported in the literature for their synthesis. Therefore, we became interested in developing a convenient synthetic method for the preparation of imidazoquinazolinone and amide derivatives. Objective: NiFe2O4@SiO2 @glucose amine were synthesized, characterized and have been used for the green, effective and mild multicomponent synthesis of quinazolinones, benzoimidazo[1,2-a]pyrimidinones and amides under solvent-free conditions in short reaction times and excellent yields. To expand of the scope of this avenue, multicomponent synthesis of mono and bis novel amides was tested for the first time. All of the products were characterized by mp, FT-IR, NMR and elemental analysis. Methods: Aldehyde (1mmol), 2-amino benzimidazole (1 mmol), dimedone (1mmol) or indane-1,3-dione (1 mmol) for the synthesis of quinazoline or imidazopyrimidinones and arene (1mmol), anhydride (1mmol), 2- aminobenzimidazole (1mmol) for the synthesis of amides in the nanocatalyst NiFe2O4@SiO2@glucose amine (0.15mol%: 0.05g) were stirred by a magnet for the required reaction time. After completion of the reaction, as indicated by TLC, the products were collected and recrystallized from ethanol if necessary. Results: We present a novel avenue for the synthesis of benzimidazo[1,2-a] pyrimidinones, quinazolinones and amides in the presence of NiFe2O4@SiO2@glucose amine under solvent-free conditions. Conclusion: In conclusion, we developed NiFe2O4@SiO2 @glucose amine-catalysed multicomponent synthesis of quinazolinones and imidazo[1,2-a]pyrimidinones using the reaction of benzaldehyde, dimedone or indane-dione and 2-aminobenzimidazole and multicomponent synthesis of amides using arenes, cyclic anhydrides and 2-aminobenzimidazole by a solvent-free technique. This method proves to be a robust and innovative approach for the synthesis of a biologically important structure. The operational simplicity, the excellent yields of products, ease of separation and recyclability of the magnetic catalyst, waste reduction and high selectivity are the main advantages of this method. Furthermore, this new avenue is cheap and environmentally benign.


RSC Advances ◽  
2018 ◽  
Vol 8 (44) ◽  
pp. 24819-24826 ◽  
Author(s):  
N. K. R. Bogireddy ◽  
U. Pal ◽  
L. Martinez Gomez ◽  
V. Agarwal

Size dependent catalytic activity of AuNPs synthesized at room temperature from Coffea arabica seed extract.


Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1000
Author(s):  
Iqbal ◽  
Sadiq ◽  
Sadiq ◽  
Ullah ◽  
Fazal ◽  
...  

A simple and practical procedure has been adopted for one pot synthesis of benzimidazole derivatives under mild reaction conditions, starting from cinnamyl alcohol (COH) with bimetallic nanoparticles (BNPs) and supported bimetallic nanoparticles of Cu, Ti, Zn, Mn, Ag, and Co. All the catalysts were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), X-Ray Diffractometry (XRD), Brunauer Emmett-Teller (BET) surface area, and pore size analyzer. The products were identified/quantified with 1HNMR, FT-IR, and MS. 98% yield of substituted derivatives of benzimidazole was obtained with Cu–Ti supported on FMWCNTs in ethanol with excellent selectivity. Quantum chemical calculations of molecular reactivity of substituted cinnamaldehyde (CHO) and ortho phenylenediamine (OPD) have good consistency with experimental results. The returns of this work were the use of readily available catalysts, high yield, short reaction time, and simplicity of the process.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Thupakula Venkata Madhukar Sreekanth ◽  
Patnamsetty Chidanandha Nagajyothi ◽  
Gutturu Rajasekhara Reddy ◽  
Jaesool Shim ◽  
Kisoo Yoo

Abstract This study describes a simple, high-yield, rapid, and inexpensive route for the synthesis of cubic shape-like cerium oxide nanocubes (CeO2 NCs) using different urea concentrations (0.5, 1.0, and 2.0 g) by the hydrothermal method. The synthesized nanocubes (NCs) are labeled as CeO2 NCs-0.5, CeO2 NCs-1.0, and CeO2 NCs-2.0, corresponding to 0.5, 1.0, and 2.0 g of urea, respectively. The synthesized NCs were characterized by FT-IR, UV-visible, XRD, XPS, SEM and HR-TEM analysis. The synthesized NCs were cubic in shape with average sizes of 12, 12, and 13 nm for the CeO2 NCs-0.5, CeO2 NCs-1.0, and CeO2 NCs-2.0, respectively, obtained by the XRD analysis. The catalytic activity of the CeO2 NCs was studied for the purpose of obtaining the reduction of malachite green (MG) in the presence of sodium borohydride (NaBH4) at room temperature.


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