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.].
Synthesis, characterization, and catalytic activity in Suzuki coupling and catalase-like reactions of new chitosan supported Pd catalyst
Baran, Talat,Inanan, Tülden,Mente?, Ayfer
, p. 20 - 29 (2016)
The aim of this study is to analyze the synthesis of a new chitosan supported Pd catalyst and examination of its catalytic activity in: Suzuki coupling reactions by improving a simple, fast, and solvent-free microwave method.H2O2 decomposition reaction to find out its redox potential. Pd catalyst was synthesized using chitosan as a biomaterial and characterized with FTIR, TG/DTG, XRD, 1H NMR, 13C NMR, SEM-EDAX, ICP-OES, Uv-vis spectroscopies, and magnetic moment, along with molar conductivity analysis. Biomaterial supported Pd catalyst indicated high activity and long life time as well as excellent turnover number (TON) and turnover frequency (TOF) values in Suzuki reaction. Biomaterial supported Pd catalyst catalyzed H2O2 decomposition reaction with considerable high activity using comparatively small loading catalyst (10 mg). Redox potential of biomaterial supported Pd catalyst was still high without negligible loss (13% decrease) after 10 cycles in reusability tests. As a consequence, eco-friendly biomaterial supported Pd catalyst has superior properties such as high thermal stability, long life time, easy removal from reaction mixture and durability to air, moisture and high temperature.
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.
Graphene Oxide Catalyzed C-H Bond Activation: The Importance of Oxygen Functional Groups for Biaryl Construction
Gao, Yongjun,Tang, Pei,Zhou, Hu,Zhang, Wei,Yang, Hanjun,Yan, Ning,Hu, Gang,Mei, Donghai,Wang, Jianguo,Ma, Ding
, p. 3124 - 3128 (2016)
A heterogeneous, inexpensive, and environmentally friendly graphene oxide catalytic system for the C-H bond arylation of benzene enables the formation of biaryl compounds in the presence of aryl iodides. The oxygen functional groups in these graphene oxide sheets and the addition of KOtBu are essential for the observed catalytic activity. Reactions with various model compounds and DFT calculations confirmed that these negatively charged oxygen atoms promote the overall transformation by stabilizing and activating K+ ions, which in turns facilitates the activation of the C-I bond. However, the graphene π system also greatly facilitates the overall reaction as the aromatic coupling partners are easily adsorbed.
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.
Visible Light Photoredox Catalyzed Biaryl Synthesis Using Nitrogen Heterocycles as Promoter
Xu, Zhen,Gao, Li,Wang, Lele,Gong, Meiwei,Wang, Wenfeng,Yuan, Rusheng
, p. 45 - 50 (2015)
Although transition-metal-catalyzed direct arylation of aromatic C-H bonds is one of the most efficient ways for the construction of biaryl targets, it is also expected for other alternative methods that can use inexpensive catalysts and abundant solar energy to drive chemical reactions. Herein, we describe a new activation mode for biaryl synthesis by using a photosensitive complex of potassium tert-butoxide (KOt-Bu) and nitrogenous heterocyclic ligands via visible light excitation. Under low-energy visible light irradiation, the single-electron transfer from electron-donor KOt-Bu to electron-deficient nitrogenous heterocycle occurred in the inner part of the complex by using potassium as a bridge atom. The ligand accepted the as-photoexcited single electron and transformed into stable radical anions which played a dominant role in the coupling reactions of benzene with aryl halides at ambient temperature. This reaction paradigm features the use of inexpensive catalyst, abundant visible light energy, and more accessible bromobenzene for the construction of biaryl compounds under rather mild conditions. (Figure Presented).
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.
1-Phosphabarrelene complexes of palladium and their use in Suzuki-Miyaura coupling reactions
Blug, Matthias,Guibert, Clément,Le Goff, Xavier-Frederic,Mézailles, Nicolas,Le Floch, Pascal
, p. 201 - 203 (2009)
A bulky 1-phosphabarrelene, 2, was obtained from the reaction of a phosphinine with benzyne; two palladium complexes of 2 were successfully employed in the Suzuki-Miyaura coupling of several aryl chlorides with phenylboronic acid at a relatively low catalyst loading, and activated aryl chlorides were coupled at room temperature in the absence of strong bases. The Royal Society of Chemistry.
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.
C?H Arylation on Nickel Nanoparticles Monitored by In Situ Surface-Enhanced Raman Spectroscopy
Li, Yonglong,Hu, Yanfang,Shi, Faxing,Li, Haixia,Xie, Wei,Chen, Jun
, p. 9049 - 9053 (2019)
Bifunctional Au@Ni core–satellite nanostructures synthesized by a one-step assembly method were employed for in situ surface-enhanced Raman spectroscopic (SERS) monitoring of Ni-catalyzed C?C bond-forming reactions. Surprisingly, the reaction that was thought to be an Ullmann-type self-coupling reaction, was found to be a cross-coupling reaction proceeding by photoinduced aromatic C?H bond arylation. In situ SERS monitoring enabled the discovery, and a series of biphenyl compounds were synthesized photocatalytically, and at room temperature, using cheap Ni nanoparticle catalysts.
