2113-56-6Relevant articles and documents
Production and Application of Highly Efficient and Reusable Palladium Nanocatalyst Decorated on the Magnetically Retrievable Chitosan/Activated Carbon Composite Microcapsules
Baran, Talat
, (2019)
Abstract: This study reports (i) the production of magnetically retrievable microcapsules as immobilizing agents, which are composed of chitosan/activated carbon composite (CS-AC/Fe3O4), (ii) the green synthesis of highly stable palladium nanoparticles on CS-AC/Fe3O4 without using any toxic reducing agents (Pd NPs@CS-AC/Fe3O4), (iii) the investigation of catalytic behavior of Pd NPs@CS-AC/Fe3O4 in Suzuki–Miyaura reactions of different aryl iodides, bromides, and chlorides, and (iv) the examination of recoverability and reusability of Pd NPs@CS-AC/Fe3O4. The characterization of Pd NPs@CS-AC/Fe3O4 was performed by FT-IR, TG/DTG, XRD, SEM, and EDS analyses. It was found that the average sizes of palladium nanoparticles were changed in the range of 31–48?nm. The catalytic tests revealed that Pd NPs@CS-AC/Fe3O4 was a very effective catalyst against synthesis of various biaryl compounds via Suzuki–Miyaura reactions, by giving high reaction yields under mild reaction conditions. Furthermore, it was found that Pd NPs@CS-AC/Fe3O4 was a highly retrievable and practical nanocatalyst due to its reusable nature. Pd NPs@CS-AC/Fe3O4 gave 95% of yield after ten successive cycles. These results show that Pd NPs@CS-AC/Fe3O4 is a superb catalyst and it can be applied in different catalytic systems or industrial applications due to the fact that it offers notable advantages such as high catalytic performance, reusability, stability, excellent functional group tolerance, wide substrate scope, and simple separation. Graphical Abstract: [Figure not available: see fulltext.].
Palladium nanoparticles-decorated triethanolammonium chloride ionic liquid-modified TiO2 nanoparticles (TiO2/IL-Pd): A highly active and recoverable catalyst for Suzuki–Miyaura cross-coupling reaction in aqueous medium
Veisi, Hojat,Kamangar, Sheida Ahany,Mohammadi, Pourya,Hemmati, Saba
, (2019)
In this work, an easily obtained procedure was successfully implemented to prepare novel palladium nanoparticles decorated on triethanolammonium chloride ionic liquid-functionalized TiO2 nanoparticles [TiO2/IL-Pd]. Different methods were carried out for characterizations of the synthesized nanocatalyst (HR-TEM, XPS, XRD, FE-SEM, EDX, FT-IR and ICP). TiO2/IL-Pd indicated good catalytic activity for the Suzuki–Miyaura cross-coupling reaction of arylboronic acid with different aryl halides in aqueous media at ambient temperature. The recycled catalyst was investigated with ICP to amount of Pd leaching after 6 times that had diminished slightly, Thus, was confirmed that the nanocatalyst has a good sustainability for C–C Suzuki–Miyaura coupling reaction. The catalyst can be conveniently separated by filtration of the reaction mixture and reused for 6 times without significant loss of its activity. It supplies an environmentally benign alternative path to the existing protocols for the Suzuki–Miyaura reaction.
Sustainable chitosan/starch composite material for stabilization of palladium nanoparticles: Synthesis, characterization and investigation of catalytic behaviour of Pd@chitosan/starch nanocomposite in Suzuki–Miyaura reaction
Baran, Talat,Y?lmaz Baran, Nuray,Mente?, Ayfer
, (2018)
We fabricated a green chitosan/starch composite as support material for stabilization of palladium nanoparticles for the first time. The chemical structure of the sustainable palladium nanocomposite was investigated using various techniques. Characterization studies showed that the average dimensions of the palladium nanocomposite ranged between 16 and 21?nm. The synthesized palladium nanocomposite was employed in the synthesis of a series of biphenyl compounds via Suzuki–Miyaura cross-coupling reactions with an unconventional technique. All coupling reactions were conducted in very short reaction time and excellent biphenyl yields were obtained in the presence of the nanocomposite. The palladium catalyst was tolerant to a wide range of functional groups. We also investigated the recyclability and reusability of the palladium nanocomposite, and found that it could be used for seven successive cycles.
Post-synthetic modification of IRMOF-3 with an iminopalladacycle complex and its application as an effective heterogeneous catalyst in Suzuki-Miyaura cross-coupling reaction in H2O/EtOH media at room temperature
Nouri, Fatemeh,Rostamizadeh, Shahnaz,Azad, Mohammad
, p. 286 - 293 (2017)
A novel iminopalladacycle complex was successfully immobilized onto a metal–organic framework (MOF) through post-synthetic modification of IRMOF-3. Initially, the IRMOF-3 was modified with benzaldehyde to achieve a Schiff-base moiety in the pores of IRMOF-3 (IRMOF-3-BI) which could anchor the palladium by the addition of palladium acetate (IRMOF-3-BI-Pd). The catalyst was fully characterized by using a variety of methods such as attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), energy dispersive X-ray (EDX), inductively coupled plasma atomic emission spectroscopy (ICP-AES), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). Also, the structural unities of MOFs have been confirmed by scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis. Moreover, the prepared catalyst has exceptionally shown excellent turnover frequencies (up to 300,000) as a heterogonous catalyst in the Suzuki C-C coupling reaction for aryl iodides, bromides and chlorides in H2O/EtOH media at room temperature. Additionally, the catalyst can be easily isolated from the reaction mixture and recycled for five sequential runs without incredible decrease in catalytic efficiency.
Iron/iron oxide nanoparticles: A versatile support for catalytic metals and their application in Suzuki-Miyaura cross-coupling reactions
Zhou, Shuai,Johnson, Melanie,Veinot, Jonathan G. C.
, p. 2411 - 2413 (2010)
Iron/iron oxide core-shell nanoparticles (Fe@FexOy) are a versatile support for immobilizing catalytic metals. Fe@Fe xOy decorated with Pd (Fe@FexOy/Pd) exhibits high catalytic activity toward Suzuki-Miyaura cross-coupling reactions in aqueous solution at room temperature in air. The Royal Society of Chemistry.
PEPPSI-type complexes with small NHC ligands obtained according to the new method efficiently catalyzed Suzuki-Miyaura reaction
Sikorski,Zawartka,Trzeciak
, p. 323 - 332 (2018)
A series of 13 new PEPPSI-type complexes with small NHC ligands and differently substituted imidazoles were prepared using as substrates [Pd(μ-X)X(bmim-y)]2 dimer or imidazole complexes PdCl2(imidazole)2. Improvement of th
Nanocellulose Supported PdNPs as in situ Formed Nano Catalyst for the Suzuki Coupling Reaction in Aqueous Media: A Green Approach and Waste to Wealth
Aabaka, Sreenath Reddy,Mao, Jincheng,Lavanya, Mallu,Venkateswarlu, Katta,Huang, Zhiyu,Mao, Jinhua,Yang, Xiaojiang,Lin, Chong
, (2021)
An effective and highly sustainable method has been developed for the Suzuki coupling reaction of aryl halides and phenylboronic acid using in situ generated nacocellulose (NC) supported palladium nanoparticles (Pd@NC NPs) as heterogeneous catalysts in water. The formation of PdNPs was observed in the absence of additional reagents, during the course of the Suzuki reaction from NC and Pd(OAc)2. In situ formed Pd@NC NPs have been systematically characterized using TEM, EDX, XRD and FT-IR techniques. The in situ generated catalyst was separated and studied for its successful reusability up to 11 cycles. The application of aqueous media, use of in situ formed catalyst, mild reaction conditions, absence of volatile organic solvents, broad substrate scope, high product isolated yields are the significant developments of this protocol. The nanocellulose used for this protocol has been generated form the waste cotton cloth and hence it is an example for the waste to wealth and sustainable approach.
Preparation of monodentate phosphinite ligands: their applications in palladium catalyzed Suzuki reactions
Cheng, Yan-Huei,Weng, Chia-Ming,Hong, Fung-E.
, p. 12277 - 12285 (2007)
Two phosphinites 2,6-OMe, 4-Me, 1-OPR2C6H2 (5a: R=Ph; 5b: R=tBu) were prepared in good yields. Two methoxy groups are placed on the 2,6 positions of the phosphinites deliberately thereby to avoid a plausible orthometallation process while coordinating toward palladium metal. Further reaction of 5a with PdCl2 in the ratio of 2:1 and 1:1 gave 5a ligated palladium complexes {(5a)PdCl(μ-Cl)}2 7a and {(5a)2PdCl2} 8a, respectively. As revealed from their crystal structures, the former is a dimeric complex with anticipated molecular arrangement; nevertheless, the latter is a monomeric complex with unexpected, energetically unfavorable cis form. By contrast, only dimeric form was observed from the reaction of 5b with PdCl2. It is believed that the bulky substituents, tBu, on 5b prevent the formation of a monomeric complex in cis form. Fair to good efficiencies were observed for the Suzuki-Miyaura cross-coupling reactions employed in situ-prepared 5/Pd(OAc)2 as the catalytic precursor.
Composition Control Synthesis and Catalytic Properties in the Suzuki Reaction of Bimetallic PdSn Nanoparticles
Li, Yong,Wang, Tian,Yang, Bo,Tian, Xi-Ke
, p. 3 - 10 (2016)
We have successfully prepared 6.5 nm palladium tin (PdSn) alloy nanoparticles (NPs) with tunable compositions by high-temperature reduction of tin acetate and palladium bromide in the presence of oleylamine and trioctylphosphine. The catalytic activities of PdSn NPs with different compositions were evaluated through Suzuki reactions. The PdSn nanocatalysts show better catalytic activity on Suzuki reactions than an equal amount of pure Pd NPs, and their catalytic activities are highly composition dependent. Among these NPs, Pd63Sn37/C NPs exhibited the highest catalytic performance with higher reaction activity, lower Pd leaching properties, and higher stability even after eight recycle reactions.
Fabrication and application of cellulose Schiff base supported Pd(II) catalyst for fast and simple synthesis of biaryls via Suzuki coupling reaction
Y?lmaz Baran, Nuray,Baran, Talat,Mente?, Ayfer
, p. 36 - 44 (2017)
Bio-supported catalysts, due to their green nature, are promising materials for coupling reactions. In this paper, the design and application of a new green cellulose Schiff base supported Pd(II) catalyst (CL-Sc-Pd) for the synthesis of different biaryls under microwave irradiation without the use of any organic solvent is reported. Firstly, a silane-modified cellulose Schiff base (CL-Sc) was synthesized as a support material, and then its heterogonous Pd(II) catalyst was easily prepared in water for the Suzuki coupling reaction. The synthesized materials were then characterized with various analytical tools. Finally, the catalytic performance of the green catalyst was investigated towards various C[sbnd]C reactions using a green, simple and fast microwave technique. The catalyst indicated excellent selectivity and activity in a very short time (6?min) under a solvent-free media. In addition, outstanding TON (19,800) and TOF (198,000) values were obtained with the green Pd(II) catalyst. The longevity of the green Pd(II) catalyst was studied and it was found to be reusable for at least eight runs. CL-Sc-Pd catalyst showed perfect catalytic efficiency for the Suzuki C[sbnd]C reaction when it was compared to commercial palladium catalysts.
Highly efficient, quick and green synthesis of biarlys with chitosan supported catalyst using microwave irradiation in the absence of solvent
Baran, Talat,A?iks?z, Eda,Mente?, Ayfer
, p. 189 - 198 (2016)
The aim of this study was to develop a quick reaction that had high activity with a small amount of catalyst, which could be an eco-friendly alternative technique for the synthesis of biarlys in Suzuki coupling reactions. First, a novel chitosan Schiff base supported Pd(II) catalyst was synthesized, and its structure was illuminated with FTIR, 1H NMR, 13C NMR, TG/DTG, SEM/EDAX, XRD, ICP-OES, UV-vis, magnetic moment, and molar conductivity techniques. Subsequently, the catalytic activity of the catalyst was tested in Suzuki C-C reactions under microwave irradiation using a solvent-free reaction condition. The catalytic tests showed an excellent activity with a small load of the catalyst (0.02 mol%) in 4 min. The catalyst showed seven runs without loss of activity, and high values of turnover numbers (TON) and turnover frequency (TOF) were obtained. The novel biopolymer supported Pd(II) catalyst provided much faster reaction times, higher yields, and reusability under microwave heating compared to classic heating methods.
Superparamagnetic nanoparticle-supported catalysis of Suzuki cross-coupling reactions
Stevens, Philip D.,Fan, Jinda,Gardimalla, Hari M. R.,Yen, Max,Gao, Yong
, p. 2085 - 2088 (2005)
(Figure Presented) Emulsion polymerization was examined as a novel route for the synthesis of core/shell superparamagnetic nanoparticles consisting of a highly crystalline γ-Fe2O3 core and a very thin polymeric shell wall. These nanoparticles were used as soluble supports for immobilizing Pd catalysts to promote Suzuki cross-coupling reactions. Recovery of catalysts was facilely achieved by applying a permanent magnet externally. Isolated catalysts were reused for new rounds of reactions without significant loss of their catalytic activity.
Exceptionally high turnover frequencies recorded for a new chitosan-based palladium(II) catalyst
Baran, Talat,Sargin, Idris,Mente?, Ayfer,Kaya, Murat
, p. 12 - 20 (2016)
To be industrially feasible, and applicable in synthesis of fine chemicals, a catalyst has to possess high turnover number (TON) and turnover frequency (TOF). In this study, a new cross-linked chitosan derivative was synthesized by using 2,2′-pyridil as a cross-linking agent. 2,2′-Pyridil cross-linked chitosan was used to as a support material for palladium catalyst. Chitosan-pyridil-based Pd(II) catalyst was tested in the microwave-assisted synthesis of biaryls via Suzuki coupling reactions. The catalyst yielded remarkable TONs of up to 20,000 and TOFs of up to 240,964 by using very low catalyst loading (5 × 10-3% mol) in a short reaction time (5 min). The catalyst also showed a better recyclability.
Eco-friendly functionalization of natural halloysite clay nanotube with ionic liquids by microwave irradiation for Suzuki coupling reaction
Massaro, Marina,Riela, Serena,Cavallaro, Giuseppe,Gruttadauria, Michelangelo,Milioto, Stefana,Noto, Renato,Lazzara, Giuseppe
, p. 410 - 415 (2014)
Microwave assisted halloysite (HNT) external surface functionalization with ionic liquids is described. HNTs modification was achieved in two steps: a) grafting of 3-mercaptopropyl trimethoxysilane on the external surface of HNT by a microwave irradiation; b) anchorage of vinylimidazolium ionic liquids by a thiol-ene reaction. MW irradiation allowed us to obtain high loading onto the HNT surface compared to those obtained through conventional synthesis. Fourier transform infrared spectroscopy and thermogravimetric analysis confirmed that the grafting has occurred only on the external surface of HNT. Turbidimetric and dynamic light scattering analyses showed that the introduction of ionic liquid on the HNT surface involves the formation of aggregates. One of these materials has been used as support for Palladium particles and tested, as catalyst, in the Suzuki reaction between phenylboronic acid and some aryl halide to give the corresponding biaryl in high yield. A catalytic efficiency higher than conventionally used support was achieved.
Pd nanoparticles stabilized on the Schiff base-modified boehmite: Catalytic role in Suzuki coupling reaction and reduction of nitroarenes
Baran, Nuray Y?lmaz,Baran, Talat,Nasrollahzadeh, Mahmoud,Varma, Rajender S.
, (2019)
Palladium nanoparticles (Pd NPs) were decorated on Schiff base-modified boehmite (Sch-boehmite) particles via a simple method without deploying any additional reducing agents and their structure was confirmed by different characterization methods. The ensuing Pd NPs?Sch-boehmite was evaluated as a retrievable catalyst for multiple cycles in Suzuki cross-coupling reactions with extensive substrate tolerance to produce biaryls in high yields within 6 min, and the reduction of 2-nitroaniline (2-NA) and 4-nitrophenol (4-NP) at room temperature in 3–4 min, respectively. Moreover, Pd NPs?Sch-boehmite catalyst could be conveniently recovered and reused multiple times.
Ultrasound-accelerated synthesis of biphenyl compounds using novel Pd(0) nanoparticles immobilized on bio-composite
Baran, Talat
, p. 231 - 237 (2018)
This study describes (i) an eco-friendly approach for design of Pd(0) nanoparticles on a natural composite, which is composed of carboxymethyl cellulose/agar polysaccharides (CMC/AG), without using any toxic reducing agents and (ii) development of ultrasound assisted simple protocol for synthesis of biphenyl compounds. Chemical characterization studies of Pd(0) nanoparticles (Pd NPs@CMC/AG) revealed that size of the particles were in the range of 37–55 nm. Catalytic performance of Pd NPs@CMC/AG was evaluated in synthesis of various biphenyl compounds by using the ultrasound-assisted method that was developed in this study. Pd NPs@CMC/AG exhibited excellent catalytic performance by producing high reaction yields. In addition, Pd NPs@CMC/AG was successfully used up to six reaction cycles without losing its catalytic activity, indicating high reproducibility of Pd NPs@CMC/AG. Additionally, compared to conventional the methods, new ultrasound-assisted synthesis technique that was followed in this study exhibited some advantages such as shorter reaction time, greener reaction conditions, higher yields and easier work-up.
Facile synthesis of NC(sp3)O pincer palladium complexes and their use as efficient catalysts for Suzuki-Miyaura reaction of aryl bromides in aqueous medium
Gong, Jun-Fang,Li, Nan,Pan, Ya-Ping,Song, Mao-Ping,Yang, Jing-Jing,Zhu, Zhi-Wu
, (2021)
Two NC(sp3)O pincer palladium(II) complexes 3a-3b were readily prepared in high yields in only two steps. Of the first step, catalytic hydrophosphination of 2-alkenoylpyridines and subsequent in situ phosphine oxidation produced the NC(sp3)O pincer preligands 2a-2b. The second step is palladation of the preligands 2a-2b where PdCl2 was used as the Pd source to afford the desired Pd pincers 3a-3b via C(sp3)-H bond activation. Single crystal X-ray diffraction analysis of complex 3a unambiguously confirmed the NCO tridentate coordination mode of the complexes. The two complexes 3a-3b were applied to catalyze the Suzuki-Miyaura reaction. Complex 3b was found to be more efficient and exhibited very high activity in the Suzuki reaction of structurally diverse aryl bromides with arylboronic acids in aqueous ethanol under air. At a reaction temperature of 70 °C, a TON of up to 1.9 × 105 and a TOF of up to 9800 h?1 were achieved. At lower temperatures 3b was still very active, giving a TON of up to 9.5 × 103 and a TOF of up to 3900 h?1 at room temperature.
Palladium nanoparticles stabilized by phosphine ligand for aqueous phase room temperature suzuki-Miyaura coupling
Ge, Jiyuan,Jiang, Jian,Yuan, Chenhuan,Zhang, Chaozhi,Liu, Minghua
, p. 1142 - 1145 (2017)
Water soluble phosphine ligand triphenylphosphine-3,3′,3″-trisulfonic acid trisodium salt (TPPTS) was used as the stabilizer as well as the activator to the palladium nanoparticles, which showed a high catalytic performance for aqueous phase Suzuki-Miyaura coupling reaction at room temperature.
Highly active, air-stable palladium catalysts for the C-C and C-S bond-forming reactions of vinyl and aryl chlorides: Use of commercially available [(t-Bu)2P(OH)]2PdCl2, [(t-Bu)2P(OH)PdCl2]2, and [[(t-Bu)2PO···H·· ·OP(t-B0. u)2]PdCl]2 as catalysts
Li, George Y.
, p. 3643 - 3650 (2002)
Air-stable palladium complexes [(t-Bu)2P(OH)]2PdCl2, [(t-Bu)2P(OH)PdCl2]2, and [[(t-Bu)2PO···H··· OP(t-Bu)2]PdCl]2 serve as efficient catalysts for a variety of cross-coupling reactions of vinyl and aryl chlorides with arylboronic acids, arylzinc reagents, and thiols to yield the corresponding styrene derivatives, biaryls, and thioethers. 31P NMR and mechanistic studies argue that the phosphinous acid ligands in the complexes can be deprotonated in the presence of a base to yield an electron-rich anionic species, which is likely a catalyst intermediate, and dimeric [[(t-Bu)2PO···H·· ·OP(t-Bu)2]PdCl]2 was isolated and cystallographically characterized. These anionic complexes are anticipated not only to accelerate the rate-determining oxidative addition of aryl chlorides but also to stabilize the palladium complexes in the catalytic cycle.
Cobalt-Catalyzed Cross-Coupling Reactions of Aryl Triflates and Lithium Arylborates
Duong, Hung A.,Yeow, Zong-Han,Tiong, Yong-Lun,Mohamad Kamal, Nur Haidah Binte,Wu, Wenqin
, p. 12686 - 12691 (2019)
A catalyst system comprising CoCl2/IAd·HBF4 enables the Suzuki-Miyaura cross-coupling reaction of a broad range of aryl triflates and arylboronic esters that are activated by n-butyllithium.
Palladium supported on cross-linked imidazolium network on silica as highly sustainable catalysts for the Suzuki reaction under flow conditions
Pavia, Cinzia,Ballerini, Eleonora,Bivona, Lucia Anna,Giacalone, Francesco,Aprile, Carmela,Vaccaro, Luigi,Gruttadauria, Michelangelo
, p. 2007 - 2018 (2013)
Highly cross-linked imidazolium-based materials, obtained by radical oligomerization of bis-vinylimidazolium salts in the presence of 3-mercaptopropyl-modified silica gel, were used as supports for palladium catalysts. Thanks to the high imidazolium loading these materials were able to support a high amount of the metal (10 wt%). Such materials were characterized by several techniques (13C magic angle spinning nuclear magnetic resonance, the Brunauer-Emmett-Teller technique, X-ray photoelectron spectroscopy, and transmission electron microscopy). The palladium catalysts displayed good activity allowing the synthesis of several biphenyl compounds in high yields working with only 0.1 mol% of palladium loading at 50°C in ethanol/water under batch condition. Moreover, a flow apparatus, to optimize the efficiency of the isolation of the pure products and minimize waste (E-factor), was investigated. For the first time the palladium catalyst and base (K 2CO3) were placed in two separate columns allowing an easy recovery of the products with very low E-factor values (4). Waste production was reduced by over 99% compared to classic batch conditions. Because of the high Pd loading only 42 mg of catalysts were employed in the Suzuki reaction between 160 mmol of 4-bromotoluene and 180 mmol of phenylboronic acid. No loss in activity was observed. Copyright
Highly efficient suzuki coupling of aryl chlorides in a continuous flow capillary microreactor
Jin, Jie,Cai, Min-Min,Li, Jian-Xin
, p. 2534 - 2538 (2009)
The Suzuki reactions of aryl chlorides containing both electron-donating and electron-withdrawing groups with aryl boronic acid, catalyzed by a simple non-phosphine ligand catalyst system, Pd(OAc)2/DABCO, were performed in a continuous capillary microreactor at 50C. In the microreactor, the coupling product was obtained mostly in near quantitative yield within a four hour residence time. In contrast, the conversions were only 12-69% in batch reactions.
Highly effective and recoverable Pd(II) catalyst immobilized on thermally stable Schiff base polymer containing phenol group: Production, characterization and application in Suzuki coupling reactions
Y?lmaz Baran, Nuray,Baran, Talat,Mente?, Ayfer,Karak??la, Meral,Sa?ak, Mehmet
, p. 87 - 94 (2018)
In this study, a novel highly efficient, recoverable, sustainable, and thermally stable Schiff base polymer-Pd(II) catalyst was designed for Suzuki coupling reactions in synthesis of biaryl compounds for the first time. Firstly, a novel Schiff base polymer containing phenol, Poly(4-((pyridine-2ylimino)methyl)benzene-1,3-diol) (P (4-PMB)), which was used as a support material in catalyst design, was synthesized in aqueous alkaline medium via oxidative polycondensation of 4-((pyridine-2-ylimino)methyl)benzene-1,3-diol (4-PMB) with NaOCl oxidant. The effects of oxidant concentration, polymerization temperature, and time on yield and molecular weight of the polymer were investigated. The structures of the synthesized compounds were illuminated by UV–Vis, FTIR, 1HNMR, XRD, TG/DTG, and SEM/EDAX methods. Then, Pd(II) complex of P (4-PMB) was produced, and its catalytic performance was tested in the synthesis of various biaryl compounds by Suzuki reactions using microwave irradiation technique which is a highly effective, fast, solvent-free and green method. The designed Pd(II) catalyst exhibited superior catalytic effect against syntheses of various biaryl compounds with high conversion yields (99%) and very low catalyst loading (0.01 mol%) for 5 min. Recyclability and reproducibility tests showed that the catalyst could be reused for seven successive runs without any great loss of its catalytic performance (84%).
Construction of new biopolymer (chitosan)-based pincer-type Pd(II) complex and its catalytic application in Suzuki cross coupling reactions
Baran, Talat,Mente?, Ayfer
, p. 591 - 598 (2017)
In this paper we described the fabrication, characterization and application of a new biopolymer (chitosan)-based pincer-type Pd(II) catalyst in Suzuki cross coupling reactions using a non-toxic, cheap, eco-friendly and practical method. The catalytic activity tests showed remarkable product yields as well as TON (19800) and TOF (330000) values with a small catalyst loading. In addition, the catalyst indicated good recyclability in the Suzuki C-C reaction. This biopolymer supported catalyst can be used with various catalyst systems due to its unique properties, such as being inert, green in nature, low cost and chemically durable.
A new chitosan Schiff base supported Pd(II) complex for microwave-assisted synthesis of biaryls compounds
Baran, Talat
, p. 535 - 541 (2017)
In this study, a new heterogeneous palladium (II) catalyst that contains O-carboxymethyl chitosan Schiff base has been designed for Suzuki coupling reactions. The chemical structures of the synthesized catalyst were characterized with the FTIR, TG/DTG, ICP-OES, SEM/EDAX, 1H NMR, 13C NMR, GC/MS, XRD, and magnetic moment techniques. The reusability and catalytic behavior of heterogeneous catalyst was tested towards Suzuki reactions. As a result of the tests, excellent selectivity was obtained, and by-products of homo coupling were not seen in the spectra. The biaryls products were identified on a GC/MS. In addition, it was determined in the reusability tests that the catalysts could be used several times (seven runs). More importantly, with very low catalyst loading (6?×?10?3?mol %) in very short reaction time (5?min), chitosan Schiff base supported Pd(II) complex gave high TON and TOF values. These findings showed that Schiff base supported Pd(II) catalyst is suitable for Suzuki cross coupling reactions.
Nickel-Catalyzed Direct Cross-Coupling of Aryl Sulfonium Salt with Aryl Bromide
Ma, Na-Na,Ren, Jing-Ao,Liu, Xiang,Chu, Xue-Qiang,Rao, Weidong,Shen, Zhi-Liang
, p. 1953 - 1957 (2022/03/27)
The direct cross-couplings of aryl sulfonium salts with aryl halides could be achieved by using nickel as a reaction catalyst. The reactions proceeded efficiently via C-S bond activation in the presence of magnesium turnings and lithium chloride in THF at ambient temperature to afford the corresponding biaryls in moderate to good yields, potentially serving as an attractive alternative to conventional cross-coupling reactions employing preprepared organometallic reagents.
Palladium Nanoparticles Supported on Cellulosic Paper as Multifunctional Catalyst for Coupling and Hydrogenation Reactions
Kalanthoden, Abdul Nasar,Zahir, Md. Hasan,Aziz, Md. Abdul,Al-Najar, Basmah,Rani, S. Kutti,Shaikh, M. Nasiruzzaman
, (2022/01/06)
Hallmark of a successful catalyst is its high efficiency, economic aspects, operational simplicity, extensive reusability, higher environment friendliness, and potential use in multiple industrial applications. Herein, a facile protocol involving a cataly
A Pd(II) Magnetically Retrievable Catalyst for Hiyama Reaction: Functionalization of Magnetic Mesoporous Silica via Click Reaction
Esquivel, Dolores,Mansoori, Yagoub,Mousavi, Samira,Navarro, Ma Angeles,Nuri, Ayat
, (2022/02/07)
Abstract: A nitrogen ligand, i.e. 1,3-di-(o-aminophenoxy)-2-propyl propargyl ether (DPPE), has been synthesized and characterized. Magnetic mesoporous silica composite (MNP@SiO2-SBA) was obtained via embedding magnetite nano-particles (MNPs) between SBA-15 channels. DPPE palladium dichloride (MNP@SiO2-SBA-DPPE-Pd(II)) was then prepared via click chemistry and fully characterized. The Hiyama reaction conditions including solvent, amount of catalyst, base and temperature were optimized for the prepared catalyst. The activity and recyclability of supported magnetic Pd(II) catalyst were evaluated under the optimal reaction conditions. The catalyst was easily separated magnetically, reused in five runs sequentially, and no significant loss of activity was observed. Graphical Abstract: [Figure not available: see fulltext.]
