scholarly journals Cu(II) and magnetite nanoparticles decorated melamine-functionalized chitosan: A synergistic multifunctional catalyst for sustainable cascade oxidation of benzyl alcohols/Knoevenagel condensation

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Zahra Alirezvani ◽  
Mohammad G. Dekamin ◽  
Ehsan Valiey
Keyword(s):  
Catalytic Activity ◽  
Knoevenagel Condensation ◽  
Ambient Pressure ◽  
Reaction Medium ◽  
Environmentally Benign ◽  
One Pot ◽  
Benzyl Alcohols ◽  
External Magnet ◽  
Multistep Synthesis ◽  
Multifunctional Catalyst

AbstractThe uniform decoration of Cu(II) species and magnetic nanoparticles on the melamine-functionalized chitosan afforded a new supramolecular biopolymeric nanocomposite (Cs-Pr-Me-Cu(II)-Fe3O4). The morphology, structure, and catalytic activity of the Cs-Pr-Me-Cu(II)-Fe3O4 nanocomposite have been systematically investigated. It was found that Cs-Pr-Me-Cu(II)-Fe3O4 nanocomposite can smoothly promote environmentally benign oxidation of different benzyl alcohol derivatives by tert-butyl hydroperoxide (TBHP) to their corresponding benzaldehydes and subsequent Knoevenagel condensation with malononitrile, as a multifunctional catalyst. Interestingly, Fe3O4 nanoparticles enhance the catalytic activity of Cu(II) species. The corresponding benzylidenemalononitriles were formed in high to excellent yields at ambient pressure and temperature. The heterogeneous Cs-Pr-Me-Cu(II)-Fe3O4 catalyst was also very stable with almost no leaching of the Cu(II) species into the reaction medium and could be easily recovered by an external magnet. The recycled Cs-Pr-Me-Cu(II)-Fe3O4 was reused at least four times with slight loss of its activity. This is a successful example of the combination of chemo- and bio-drived materials catalysis for mimicing biocatalysis as well as sustainable and one pot multistep synthesis.

A protective roasting strategy for preparation of stable mesoporous hollow CeO2 microspheres with enhanced catalytic activity for one-pot synthesis of imines from benzyl alcohols and anilines

2019 ◽  
Vol 6 (3) ◽  
pp. 829-836 ◽  
Author(s):  
Yu Long ◽  
Hongbo Zhang ◽  
Zekun Gao ◽  
Jiaheng Qin ◽  
Yiting Pan ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
One Pot ◽  
Benzyl Alcohols ◽  
One Pot Synthesis

A protective roasting strategy can be applied to prepare stable mh-CeO2 microspheres with enhanced catalytic activity and reusability for one-pot synthesis of imines.

Chitosan: A Natural and Sustainable Polymeric Organocatalyst for C-C Bond Formation During the Synthesis of 5-amino-2,3-dihydrobenzo[d] thiazole-4,6-dicarbonitriles

2019 ◽  
Vol 6 (1) ◽  
pp. 69-76
Author(s):  
Km N. Shivhare ◽  
Ibadur R. Siddiqui
Keyword(s):  
Catalytic Activity ◽  
Multicomponent Reaction ◽  
Bond Formation ◽  
Environmentally Benign ◽  
One Pot ◽  
Reaction Condition ◽  
Three Component Reaction ◽  
Efficient Route

Background: A green, recyclable and reusable chitosan catalyst has been utilized for the synthesis of 5-amino-2,3-dihydrobenzo[d]thiazole-4,6-dicarbonitrile and its derivatives. Methods and Results: Three-component reaction protocol incorporates the reaction of aldehydes, malononitrile and rhodanine derivatives. This is examined as an efficient route for the synthesis of dicarbonitriles utilizing a green, biodegradable, environmentally benign, and easily available chitosan catalyst. In the reported protocol, catalyst can be recycled and not any substantial dropping in its catalytic activity during the recycling steps was obtained. Conclusion: A green and environmentally benign, one pot three-component protocol has been illustrated for the synthesis of 5-amino-2,3-dihydrobenzo[d]thiazole-4,6-dicarbonitrile derivatives. Adequately yield products were gained via the natural catalytic approach with the recyclability of the catalyst. The use of chitosan represents this procedure as an attractive substitute for the synthesis of biaryls complex by multicomponent reaction condition.

scholarly journals Recyclable Magnetite Nanoparticle Catalyst for One-Pot Conversion of Cellobiose to 5-Hydroxymethylfurfural in Water

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Anuja Bhalkikar ◽  
Zane C. Gernhart ◽  
Chin Li Cheung
Keyword(s):  
Catalytic Activity ◽  
Magnetite Nanoparticles ◽  
Environmentally Benign ◽  
Hydrothermal Conditions ◽  
One Pot ◽  
Magnetite Nanoparticle ◽  
The One ◽  
Nanoparticle Catalyst

Environmentally benign and easily recoverable magnetite nanoparticles (Fe3O4NPs) were demonstrated to catalyze the one-pot conversion of cellobiose, a glucose disaccharide, to 5-hydroxymethylfurfural (5-HMF). The conversion was achieved in water under hydrothermal conditions. The catalytic activity of Fe3O4NPs surpassed those of iron (II) and iron (III) chlorides in this reaction. Optimized cellobiose conversion reactions catalyzed with Fe3O4NPs gave the highest 5-HMF yields of 23.4 ± 0.6% at 160°C for 24 hours. After three reuses, the Fe3O4NP catalyst retained its catalytic activity with similar 5-HMF yields, demonstrating the recyclability of this eco-friendly catalyst in water.

scholarly journals Palladium Catalyzed α,β-Homodiarylation of Vinyl Esters in Aqueous Medium

2021 ◽  
Author(s):  
Ryszard Ostaszewski ◽  
Damian Trzepizur ◽  
Anna Brodzka ◽  
Dominik Koszelewski ◽  
Monika Wilk
Keyword(s):  
Catalytic Activity ◽  
Functional Group ◽  
Reaction Medium ◽  
Environmentally Benign ◽  
Vinyl Esters ◽  
Arylboronic Acid ◽  
Reaction Conditions ◽  
Mild Conditions ◽  
Palladium Catalyzed ◽  
One Step

Abstract A palladium catalyzed 1,2-diarylation of vinyl esters with sustainable arylbornic acids in water has been developed. This newly elaborated protocol features good functional group tolerance and provides a one-step access to 1,2-diaryletahol derivatives under mild reaction conditions. The presented reaction can be carried out in water smoothly without the addition of any ligands at ambient temperature what makes this procedure environmentally benign. The transformation occurs within a single catalytic cycle and is feasible due to the modification of transition metal catalytic activity through the influence of π-acceptor olefin (benzoquinone) as well as the polar protic reaction medium (water in particular). Moreover, the protocol allows to generate entire compounds libraries (highly profitable in medicinal chemistry) and utilizes sustainable arylboronic acid as coupling partners under mild conditions.

scholarly journals H4SiW12O40Catalyzed One-Pot Synthesis of 12-Aryl-8,9,10,12-tetrahydrobenzo[a] Xanthen-11-ones Under Solvent-Free Conditions

2012 ◽  
Vol 9 (2) ◽  
pp. 786-790 ◽  
Author(s):  
A. Hassankhani ◽  
E. Mosaddegh ◽  
S. Y. Ebrahimipour
Keyword(s):  
Catalytic Activity ◽  
Solvent Free ◽  
Environmentally Benign ◽  
Reusable Catalyst ◽  
High Catalytic Activity ◽  
One Pot ◽  
Aryl Aldehydes ◽  
One Pot Synthesis ◽  
Solvent Free Conditions ◽  
The One

An efficient and environmentally benign protocol for the one-pot, three-component synthesis of 12-aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-one derivatives by condensation of aryl aldehydes, 2-naphthol and dimedone using H4SiW12O40(SiWA) as a reusable catalyst with high catalytic activity was reported. The reaction was carried out at 100 ºC under solvent-free conditions within 15-40 min in 82-91% yield.

Urea–Zinc Chloride Eutectic Mixture-Mediated One-Pot Synthesis of Imidazoles: Efficient and Ecofriendly Access to Trifenagrel

Synlett ◽  
2018 ◽  
Vol 30 (02) ◽  
pp. 225-229 ◽  
Author(s):  
Cristian Ochoa-Puentes ◽  
Natalia Higuera ◽  
Diana Peña-Solórzano
Keyword(s):  
Catalytic Activity ◽  
Aromatic Aldehyde ◽  
Zinc Chloride ◽  
Ammonium Acetate ◽  
Reaction Medium ◽  
Eutectic Mixture ◽  
One Pot ◽  
Dicarbonyl Compound ◽  
Excellent Yield ◽  
One Pot Synthesis

The low-melting mixture urea–ZnCl2 was evaluated as a novel reaction medium for the synthesis of imidazoles. The reaction between a dicarbonyl compound, ammonium acetate, and an aromatic aldehyde is efficiently catalyzed by the eutectic solvent, yielding a wide variety of triaryl-1H-imidazoles or 2-aryl-1H-phenanthro[9,10-d]imidazoles in good to excellent yields. In addition, the eutectic solvent was reused in five cycles without loss of its catalytic activity. This protocol was further explored for the synthesis of the drug trifenagrel, giving an excellent yield.

scholarly journals Nano Copper-Cobalt Ferrite Catalyzed One-Pot Green Combination of β, γ- Unsaturated Ketones by Ultrasonication Method

2020 ◽  
pp. 569-618
Keyword(s):  
Heterogeneous Catalysts ◽  
Cobalt Ferrite ◽  
Reaction Medium ◽  
Environmentally Benign ◽  
Acid Chlorides ◽  
One Pot ◽  
Unsaturated Ketones ◽  
Cobalt Ferrites ◽  
Several Intervals

Nano Copper-Cobalt ferrite materials have been used as magnetically separable and reusable heterogeneous catalysts for the synthesis of β, γ - unsaturated ketones over the allylation of acid chlorides with allyl bromides is presented. Ultrasonication method used to the reaction between substituted acid chlorides with allyl halides is carried out in attendance of Nano Copper-Cobalt ferrites at room temperature by using Tetrahydrofuran (THF) as a Solvent. The present method is environmentally benign and gives very good yields. The catalyst is separated from the reaction medium using a strong magnet and reused several intervals without the loss of much catalytic activity. The mechanism of the reaction and characterization of the products are presented

Ionic Liquid Promoted Knoevenagel and Michael Reactions

2004 ◽  
Vol 57 (11) ◽  
pp. 1067 ◽  
Author(s):  
Xuesen Fan ◽  
Xueyuan Hu ◽  
Xinying Zhang ◽  
Jianji Wang
Keyword(s):  
Ionic Liquid ◽  
Knoevenagel Condensation ◽  
Reaction Medium ◽  
Environmentally Benign ◽  
Atom Economy ◽  
Reaction Conditions ◽  
Michael Reactions ◽  
Operation Process ◽  
Benign Nature ◽  
High Yields

The utilization of the ionic liquid [bmim][BF4] as both reaction medium and promoter for the Knoevenagel condensation and Michael addition reactions is described in this paper. Through these reactions, several useful electrophilic alkenes and chromene derivatives are obtained in high yields. The advantages of these two novel procedures include their environmentally benign nature, atom economy, simple operation process, and mild reaction conditions.

K10 montmorillonite clays as environmentally benign catalysts for organic reactions

2014 ◽  
Vol 4 (8) ◽  
pp. 2378-2396 ◽  
Author(s):  
Basuvaraj Suresh Kumar ◽  
Amarajothi Dhakshinamoorthy ◽  
Kasi Pitchumani
Keyword(s):  
Catalytic Activity ◽  
Organic Reactions ◽  
Environmentally Benign ◽  
Montmorillonite Clays ◽  
Multifunctional Catalyst

This perspective summarizes the catalytic activity of K10 montmorillonite as a multifunctional catalyst for organic reactions.

One-Pot Synthesis and Conformational Analysis of 6-Membered Cyclic Iodonium Salts

2020 ◽  
Author(s):  
Lucien Caspers ◽  
Julian Spils ◽  
Mattis Damrath ◽  
Enno Lork ◽  
Boris Nachtsheim
Keyword(s):  
Conformational Analysis ◽  
Bronsted Acids ◽  
One Pot ◽  
Benzyl Alcohols ◽  
Iodonium Salts ◽  
Efficient Approach ◽  
One Pot Synthesis ◽  
Diaryliodonium Salts

In this article we describe an efficient approach for the synthesis of cyclic diaryliodonium salts. The method is based on benzyl alcohols as starting materials and consists of an Friedel-Crafts-arylation/oxidation sequence. Besides a deep optimization, particluar focusing on the choice and ratios of the utilized Bronsted-acids and oxidants, we explore the substrate scope of this transformation. We also discuss an interesting isomerism of cyclic iodonium salts substituted with aliphatic substituents at the bridge head carbon. <br>

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