Suzuki Reaction In Water Research Articles

Recyclable polyethylenimine based polymer for selective Pd(II) recovery and Suzuki reaction: Waste to treasure tactics

Developing efficient materials for the selective capture of Pd(II) from secondary sources, along with the reutilization of spent Pd(II)-loaded adsorbents, is of great significance, but remains great challenging. Herein, a highly efficient adsorbent (TP@PEI) was fabricated through polycondensation of polyethyleneimine (PEI) with 1,3,5-triformylphoroglucinol (TP), which selectively extracts palladium ions from simulated industrial wastewater, with preferential uptake of Pd(II) over 9 competing cations. The TP@PEI achieves ultrafast capture of Pd(II) in just 20 min, with an impressive adsorption capacity of 620 mg g−1. Of greater significance, the removal efficiency for Pd(II) reaches 99.9 % at a concentration of 100 mg L-1, which still remains at a remarkable 99 % after 11 adsorption–desorption cycles. Exceptional 99.9 % Pd(II) recovery is achieved through the adsorption of a depleted Pd-digested solution, while the breakthrough test validates its practicality and impressive bed breakthrough time (1070 min). Mechanism study reveals that the exceptional adsorption performance of TP@PEI for palladium is driven by synergistic interactions, including coordination and electrostatic interactions. Furthermore, the waste Pd(II) loaded TP@PEI efficiently catalyzes the Suzuki reaction in water, achieving a remarkable 99 % yield of the targeted compound. This research showcases a strategy for converting industrial waste into a valuable resource by meticulously engineering materials to extract precious metals from wastewater, subsequently repurposing them as high-performing catalysts.

A new β-cyclodextrin-based nickel as green and water-soluble supramolecular catalysts for aqueous Suzuki reaction

A water-soluble nickel complex based on amino-β-CD was developed using a facile method and exhibits excellent catalytic performance in the Suzuki reaction in water. This synthesized complex has been characterized using UV–Vis, AAS, TGA, and FT-IR techniques. The easily synthesized novel supramolecular catalysts have been applied as a green and eco-friendly catalyst in the Suzuki coupling for preparing diverse biaryls. This result indicates that using 2.5 mol% of nickel, K2CO3 as the best base, and water as the green solvent are the best reaction conditions. This new catalyst features easy handling, low-cost, mild, and simple protocol. The use of low-cost and accessibility of the reagents, modest conditions, and good yields of products are notable characteristics of this method. Using aqueous media with this catalyst as a proper catalyst makes the presented process a fascinating method compared to most reports. Under mild reaction conditions, this green Ni(II)-β-CD catalyst displayed recyclable behavior seven times with minor loss in its catalytic activity.

An Efficient Recyclable Polymer Supported Palladium Catalyst for Suzuki Reaction in Water

AbstractThis work describes the development of an efficient and reusable heterogeneous polymer supported palladium catalyst for Suzuki reaction in water. This novel catalyst system was designed through monoethanolamine (MEA) modification of nitrile group in Polyacrylonitrile (PAN) followed by metal salt (PdCl2) complexation. The resulting polymer complex (mPAN‐Pd) was then successfully optimised as an efficient heterogeneous catalyst for Suzuki reaction under ligand free conditions. The supported catalyst provided excellent reactivity in the coupling reactions of a series of aryl halides with phenyl boronic acids under mild reaction condition. The reaction proceeded in presence of 2 mol % ofmPAN‐Pdcatalyst at 80 °C in water and the resulting products were isolated in moderate to excellent yields upto 98 %. Furthermore, this catalyst can be conveniently recovered by simple filtration and reused at least five times without an appreciable loss in its activity or Palladium leaching.

Selective capture of Pd(II) from aqueous media by ion-imprinted dendritic mesoporous silica nanoparticles and re-utilization of the spent adsorbent for Suzuki reaction in water

The development of highly efficient adsorptive material for the selective capture of Pd(II), and re-utilization of spent Pd(II)-loaded adsorbent as an efficient catalyst for organic synthesis are of great significance, but challenging. Particularly, the heterogeneous palladium-catalyzed Suzuki reaction in aqueous media is much more challenging than that of homogeneous. Herein, several novel Pd(II) ion-imprinted polymers (PIIPs) based on dendritic fibrous silica particles are constructed by surface ion imprinting technology (SIIT), using Schiff base and pyridine groups functionalized organosilicon as functional monomer. The PIIP-3 prepared by 3 g of functional monomer exhibits the best adsorption performance, and shows ultrafast (10 min) and selective capture of Pd(II) with high uptake capacity (382.5 mg/g). Moreover, the waste Pd(II) loaded PIIP-3 (PIIP-3-Pd) can serve as a catalyst towards the Suzuki reaction in water, affording 94.2 % yield of the desired product. Interestingly, the PIIP-3-Pd can be reused 12 times without an appreciable decrease in catalytic activity, which is probably due to the imprinted cavity and specific recognition site of PIIP-3 can match and recapture Pd active species in a complex catalytic environment. Thus, this work demonstrates huge potentials of SIIT to enhance the selectivity of adsorption process and increase the lifetime of catalysts.

Reusable Proline-Containing Bimetallic Pd–Ni(Co, Cu, Fe)–Pro/Al2O3 Catalysts for Suzuki Reaction in Water

Bimetallic proline-containing composites Pd–Ni(Co, Cu, Fe)–Pro/Al2O3, due to the synergistic effect, exhibit high catalytic activity in the Suzuki reaction in aqueous media, which makes it possible to reduce the amount of expensive Pd to 10–2 mol %. New catalysts are easily regenerated from the reaction mixture and can be reused up to 5 times without losing activity.

Compatible with excellent gold/palladium trap and open sites for green Suzuki coupling by an imidazole-modified MOF

Aiming for materials compatible with enhanced gold/palladium trap and open active sites for green Suzuki coupling, Zr- L1 / L2 of UiO-66 topology was feasibly modified with amine and imidazole α-diimine side-groups. Excellent extraction percentage (>98%), high selectivity and outstanding recyclability were obtained by the adsorbent in recovering gold from river water. The saturate adsorption capacity was calculated to reach 1582.5 mg g −1 , outperforming most reported sorbents. Furthermore, up to 99% palladium recovery performance in less than 5 min was achieved. Palladium-loaded sample exhibit perfect conversion and excellent recyclability for aqueous-phase Suzuki coupling at room temperature. In this study, the synergistic interactions (coordination, electrostatic interaction and hydrogen bonding) in the material benefit for the remarkable extraction performance of gold and palladium in river, preventing palladium leaching out and aggregation. • Excellent gold adsorption capability was achieved. • Ultrafast palladium recovery behaviours was observed. • The palladium-embedded material was employed as a highly efficient catalyst for Suzuki reactions in water. • Synergistic interactions provide metal traps and prevent palladium leaching out and aggregation as well.

Selective Capture of Pd(Ii) from Aqueous Media by Ion-Imprinted Dendritic Mesoporous Silica Nanoparticles and Re-Utilization of the Spent Adsorbent for Suzuki Reaction in Water

Selective Capture of Pd(Ii) from Aqueous Media by Ion-Imprinted Dendritic Mesoporous Silica Nanoparticles and Re-Utilization of the Spent Adsorbent for Suzuki Reaction in Water

A fluorescence active catalyst support comprising carbon quantum dots and magnesium oxide doping for stabilization of palladium nanoparticles: Application as a recoverable catalyst for Suzuki reaction in water

Novel magnesium oxide-carbon quantum dots are synthesized and used for the formation and stabilization of palladium nanoparticles. This highly water dispersible material, Pd@MgO-CQD, has been used as an active catalyst for Suzuki coupling of aryl bromides at room temperature and aryl chlorides at 80°C in water. Using fluorescence emission of the material, a new protocol for determining Pd loading and leaching in catalyst preparation and recycling process is developed.

Highly Dispersed Palladium Nanoparticle-Loaded Magnetic Catalyst (FeS@EP–AG–Pd) for Suzuki Reaction in Water

In this work, an efficient epichlorohydrin–aminoguanidine-modified Fe3O4@SiO2 magnetic nanoparticles (FeS@EP–AG–Pd) with highly dispersed Palladium nanoparticles (Pd NPs) was reported for Suzuki reaction in water. After preparation of Fe3O4@SiO2 (FeS), special epichlorohydrin–aminoguanidine linker as a ligand with high content of heteroatoms was covalently bonded onto the FeS MNPs to increase their electron density. PdII ions were then loaded on surface of FeS@EP–AG MNPs and reduced for achieving the uniformly dispersed Pd NPs. FeS@EP–AG–Pd MNPs were performed in Suzuki reaction as an efficient catalyst in water as a green non-toxic solvent. Magnetically separable and recyclable FeS@EP–AG–Pd MNPs were then fully characterized by FTIR, SEM, TEM, TGA, VSM, XRD, and ICP–OES. The heterogeneous catalyst could also easily be recovered and reused with no loss of activity over 6 cycles.

Palladium-Catalyzed Suzuki Reactions in Water with No Added Ligand: Effects of Reaction Scale, Temperature, pH of Aqueous Phase, and Substrate Structure

The heterogeneous palladium-catalyzed Suzuki reactions between model aryl bromides (4-bromoanisole, 4-bromoaniline, 4-amino-2-bromopyridine, and 2-bromopyridine) and phenylboronic acid have been successfully conducted in water with no added ligand at the 100 mL scale using 20–40 mmol of aryl bromide. The product yields associated with these substrates were optimized, and key reaction parameters affecting the yields were identified. The results clearly indicate that the reaction parameters necessary to achieve high yields are substrate-dependent. In addition, it is demonstrated that aqueous Suzuki reactions of substrates containing basic nitrogen centers can produce quantitative yields of desired products in the absence of added ligand.

Nano tetraimine Pd(0) complex as an efficient catalyst for phosphine‐free Suzuki reaction in water and copper‐free Sonogashira reaction under aerobic conditions

A nano tetraimine Pd(0) complex catalyst was successfully used as an efficient heterogeneous catalyst for the phosphine‐free palladium‐catalysed Suzuki coupling reaction in water at 80 °C. This nano tetraimine Pd(0) complex was also used for copper‐free Sonogashira reaction in dimethylformamide at 100 °C. The catalyst was easily recovered from the reaction mixture by centrifugation and reused for at least six cycles without any significant loss in its catalytic activity. Analysis of the reaction mixture using inductively coupled plasma analysis showed that leaching of palladium from the catalyst was negligible. The reactions can be performed efficiently for aryl iodides, bromides and also chlorides. Copyright © 2016 John Wiley & Sons, Ltd.

ChemInform Abstract: Ligand‐Free Pd/C‐Catalyzed One‐Pot, Three‐Component Synthesis of Aryl‐Substituted Benzimidazoles by Hydrogen‐Transfer and Suzuki Reactions in Water.

AbstractAn efficient protocol is developed for the ligand‐free and heterogeneous Pd‐C‐catalyzed one‐pot, three‐component synthesis of aryl‐substituted benzimidazoles from benzyl alcohols by using water as the solvent.

Ligand‐Free Pd/C‐Catalyzed One‐Pot, Three‐Component Synthesis of Aryl‐Substituted Benzimidazoles by Hydrogen‐Transfer and Suzuki Reactions in Water

AbstractAn efficient protocol for the ligand‐free and heterogeneous Pd/C‐catalyzed one‐pot, three‐component synthesis of aryl‐substituted benzimidazoles from benzyl alcohols by using water as the solvent was developed. The reaction involves hydrogen‐transfer and Suzuki reactions. This method is quite convenient and environmentally friendly.

ChemInform Abstract: Arylation of Pyridine N‐Oxides via a Ligand‐Free Suzuki Reaction in Water.

Abstract We report a practical and highly efficient protocol for the arylation of pyridine N -oxides with arylboronic acid through palladium-catalyzed Suzuki reaction in water. This ligand-free Suzuki reaction is performed in the presence of diisopropylamine and gives 2- or 3-arylated pyridyl N -oxide derivatives in good to excellent yields within 1 h.

Pd/PdO nanoparticles supported on carbon nanotubes: A highly effective catalyst for promoting Suzuki reaction in water

We report that the presence of PdO nanoparticles can enhance the catalytic performance of Pd catalyst for the Suzuki reaction in water. Heterogeneous Pd/PdO nanoparticles supported on multi-walled carbon nanotubes (CNTs), weakly oxidized multi-walled carbon nanotubes (WCNTs) and strongly oxidized multi-walled carbon nanotubes (SCNTs) catalysts are synthesized by a one-pot gas–liquid interfacial plasma (GLIP) method using Pd(NO3)2·2H2O as precursor. Among these synthesized catalysts, the Pd/PdO supported on WCNTs (Pd/PdO/WCNTs) catalyst exhibits the highest catalytic activity during the Suzuki reaction in water. Moreover, the Pd/PdO catalyst shows higher catalytic activity during the Suzuki reaction than Pd catalyst. The as-prepared catalyst displayed remarkable activity toward challenging substrates such as heteroaryl halides and ortho-substituted aryl halides as well as aryl chlorides using low Pd loading in good yields. Since the catalyst exhibits extremely low solubility in organic solvent, the product can be simply extracted with ethyl acetate while the catalyst remained in the aqueous phase. The catalyst can be simply and efficiently used for ten consecutive runs without significant decrease in activity.

Pd Nanoparticles Immobilized on Orange-Like Magnetic Polymer-Supported Fe3O4/PPy Nanocomposites: A Novel and Highly Active Catalyst for Suzuki Reaction in Water

An orange-like catalyst of Pd nanoparticles supported by magnetic Fe3O4/polypyrrole nanocomposite is facilely prepared. It shows great activity for Suzuki coupling reactions in neat water under atmospheric pressure. This magnetic and water-soluble catalyst avoids the use of toxic solvents in traditional process of coupling reactions and can be easily recovered by mean of a convenient magnetic separation technique, demonstrating in both environmental friendliness and recyclability.

Exhibition of the Brønsted acid-base character of a Schiff base in palladium(II) complex formation: lithium complexation, fluxional properties and catalysis of Suzuki reactions in water.

The reaction of the dialdehyde N,N-di(α-formylpyrrolyl-α-methyl)-N-methylamine with two equiv. of 2,6-diisopropylaniline yielded two Schiff bases: bis(iminopyrrolylmethyl)amine () and its hydrolyzed monoimino compound () after column separation. The dimeric lithium complex [(HL)Li]2 () containing the monoanionic form of was obtained by treating with (n)BuLi. The presence of both proton donors and acceptors causes the diimino compound to undergo tautomerization to exhibit an amine-azafulvene structure, though the central amine nitrogen competes for a proton. As a result, in the presence of Pd(2+) ions, the cationic complex [Pd(Cl)(H2L)][Cl] () containing one pendant amine-azafulvene arm and the protonated central amine nitrogen was obtained. Its X-ray structure showed that the bond distances are reversed for the imino-pyrrole moiety relative to those in the structure of . However, the reaction of with [Pd(OAc)2] afforded the neutral complex [PdL] () containing the dianionic form of the ligand. The reaction of with [PdCl2(PhCN)2] yielded a zwitterionic complex [PdCl2(H2L')] () owing to the presence of the central amine nitrogen. The formation of these palladium complexes with the features mentioned above can be explained by invoking the Brønsted acid-base character of the Schiff base. Complex is fluxional owing to the up and down movements of the palladium square plane formed by two 5-membered palladacycles, which causes the interconversion of its enantiomers and is studied by the variable temperature (1)H NMR method. Furthermore, both complexes and are precatalysts for the Suzuki-Miyaura cross-coupling reaction in water. Sterically encumbered and electronically different substrates including activated aryl chlorides and benzyl halides gave the coupled products in very good yields. The reaction proceeds even at room temperature and in the presence of a large excess amount of mercury.

Magnetic polymer nanocomposite-supported Pd: an efficient and reusable catalyst for the Heck and Suzuki reactions in water

Pd supported on magnetic polymer nanocomposites serves as an efficient and recyclable catalyst for the water-phase Heck and Suzuki reactions.

Palladium nanoparticles embedded on thiourea-modified chitosan: a green and sustainable heterogeneous catalyst for the Suzuki reaction in water

Palladium nanoparticles embedded on thiourea modified chitosan (TMC) are prepared in spherical and cubical shapes by intercalating Pd(OAc)2 in TMC, a natural bio-polymer, and a subsequent reduction using ellagic acid as a natural and green reducing source in water.

Arylation of pyridine N-oxides via a ligand-free Suzuki reaction in water

Abstract We report a practical and highly efficient protocol for the arylation of pyridine N -oxides with arylboronic acid through palladium-catalyzed Suzuki reaction in water. This ligand-free Suzuki reaction is performed in the presence of diisopropylamine and gives 2- or 3-arylated pyridyl N -oxide derivatives in good to excellent yields within 1 h.