92-69-3Relevant articles and documents
Design of a capillary-microreactor for efficient Suzuki coupling reactions
Basheer, Chanbasha,Jahir Hussain, Fathima Shahitha,Lee, Hian Kee,Valiyaveettil, Suresh
, p. 7297 - 7300 (2004)
A Pyrex glass capillary (0.4 mm internal diameter) microreactor was developed and used for Suzuki coupling reactions. Capillary-microreactors are more attractive than photolithographic microfluidic devices in terms of simplicity, low cost and ease of handling. Compared with the conventional synthesis procedure, our approach of using a capillary-microreactor offers a convenient and highly efficient means to optimize reaction conditions and the performance of catalysts. The procedure exhibits good precision, reproducibility and high reaction yield for a range of reactants investigated.
Selective heating of pd-modified ordered mesoporous carbon CMK-3 by microwave irradiation
Inagaki, Satoshi,Onodera, Kenzo,Tani, Kensaku,Kubota, Yoshihiro
, p. 1136 - 1143 (2011)
Various microwave-heated heterogeneous catalytic reactions can be accelerated by choice of the catalyst supports and solvents. In this work, heterogeneous Pd catalysts supported on ordered mesoporous carbon CMK-3 and related catalysts were prepared. In the presence of these catalysts, the effect of microwave heating on Pd-catalyzed SuzukiMiyaura coupling as a probe reaction was investigated. The CMK-3 worked efficiently as a "carbon nanoflask" under microwave irradiation, especially in nonpolar solvents such as toluene and o-xylene with a lower ratio of dielectric constant (δ′) to dielectric loss (δ″) (=tan δ).
Suzuki-miyaura reaction in water, catalyzed by palladium nanoparticles stabilized by pluronic F68 triblock copolymer
Kashin,Beletskaya
, p. 475 - 479 (2011)
Palladium nanoparticles stabilized by Pluronic F68 triblock copolymer effectively catalyzed Suzuki-Miyaura reaction in water. The reactions with water-soluble aryl iodides and aryl bromides containing electron-withdrawing or electron-donating substituent occurred at room temperature. The catalytic efficiency was found to depend on the size of palladium nanoparticles and their morphology. Pleiades Publishing, Ltd., 2011.
One-pot hydrothermal synthesis of Pd/Fe3O4 nanocomposite in HEPES buffer solution and catalytic activity for Suzuki reaction
Li, Shaozhong,Zhang, Wei,Chen, Fengxi,Chen, Rong
, p. 186 - 191 (2015)
The Pd/Fe3O4 nanocomposite integrates versatile Pd nanocatalysts with magnetic separation, and has great potential in fine chemical and pharmaceutical synthesis. Its preparation usually involves multi-steps. Herein it was prepared via a facile one-pot hydrothermal synthesis in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer solution with the assistant of polyvinylpyrrolidone (PVP). HEPES plays multi-functions, particularly as a ligand to enhance the oxidation of Fe2+ to Fe3+ and as a buffer to control the pH value at slightly basic conditions (ca. 7.4) for the formation of crystalline Fe3O4 phase via Fe2+/Fe3+ co-precipitation. PVP works as a dispersant to prevent the particle from aggregation. The obtained Pd/Fe3O4 nanocomposite comprised uniform Pd nanoparticles (ca. 5 nm) deposited on Fe3O4 nanocrystals (ca. 15 nm). It exhibited excellent catalytic activity and stability for various Suzuki coupling reactions, and could be efficiently recovered with a magnet and recycled for at least 10 cycles without losing catalytic activity.
Stabilized Palladium Nanoparticles: Synthesis, Multi-spectroscopic Characterization and Application for Suzuki–Miyaura Reaction
Patel, Anish,Patel, Anjali
, p. 3534 - 3547 (2018)
The present article demonstrates a simple method for synthesizing the highly stabilized Pd(0) nanoparticles by using supported 12-tungstophosphoric acid as a stabilizer as well as a carrier. The obtained material was characterized by different methods and the presence of nanoparticles on the surface of the carrier was confirmed, especially by TEM and XPS. As an application, the use of material was explored for the well-known fascinating organic transformation, Suzuki–Miyaura cross coupling reaction in aqueous medium as well as in neat H2O. It was found that the material shows an outstanding activity as the heterogeneous catalyst (0.0096?mol% of Pd) for both aqueous medium (99% conversion, TOF 96958?h?1) and in neat H2O (89% conversion, TOF 46390?h?1) towards biphenyl. The catalyst was recovered by filtration only, regenerated and reused without any significant loss in conversion. Study shows that the present catalyst is truly heterogeneous and sustainable for the said reaction, in either of the medium. The viability of the catalyst was learned toward different substrates and found to be excellent in almost all cases. Graphical Abstract: Pd nanoparticles stabilized by supported 12-tungstophosphoric acid is proved to be sustainable and excellent for Suzuki–Miyaura reaction with very high catalyst to substrate ratio as well as TOF. [Figure not available: see fulltext.].
Highly active Pd-Ni nanocatalysts supported on multicharged polymer matrix
Sultanova, Elza D.,Samigullina, Aida I.,Nastapova, Natalya V.,Nizameev, Irek R.,Kholin, Kirill V.,Morozov, Vladimir I.,Gubaidullin, Aidar T.,Yanilkin, Vitaliy V.,Kadirov, Marsil K.,Ziganshina, Albina Y.,Konovalov, Alexander I.
, p. 5914 - 5919 (2017)
In this article, we report the synthesis of mono- and bimetallic Pd-Ni nanocomposites supported on a multicharged polymeric matrix for catalytic applications. The morphology and catalytic properties of the composites depend on the Pd-Ni ratio. In the Suzuki-Miyaura coupling reaction, the composite with an equal amount of palladium and nickel is the most active and the reaction occurs within six hours in water at room temperature.
Anchoring of palladium(II) in chemically modified mesoporous silica: An efficient heterogeneous catalyst for Suzuki cross-coupling reaction
Bhunia, Susmita,Sen, Rupam,Koner, Subratanath
, p. 3993 - 3999 (2010)
The synthesis and characterization of a highly efficient and reusable catalyst, Pd(II) immobilized in mesoporous silica MCM-41, are described. Pd(II) Schiff-base moiety has been anchored onto mesoporous silica surface via silicon alkoxide chemistry. The catalyst has been characterized by small-angle X-ray diffraction (SAX), FTIR and electronic spectroscopy as well as elemental analysis. The catalyst is used in Suzuki cross-coupling reaction of various aryl halides, including less reactive chlorobenzene, and phenylboronic acid to give biaryls in excellent yields without any additive or ligand. High selectivity for the bi-aryl products containing both electron-donating and electron-withdrawing substituents, mild reaction conditions and possibility of easy recycle makes the catalyst highly desirable to address the industrial needs and environmental concerns.
Magnetically recyclable Fe@Pd/C as a highly active catalyst for Suzuki coupling reaction in aqueous solution
Tang, Weijie,Li, Jing,Jin, Xiaodong,Sun, Jian,Huang, Jingwei,Li, Rong
, p. 75 - 78 (2014)
In this work, a novel catalyst Fe@Pd/C was synthesized by sequential reduction method. The core-shell catalyst exhibited efficient catalytic activity in Suzuki coupling reaction at mild condition in water. Moreover, the catalyst could be recycled by external magnetic field and the yields achieved above 86% after reused at least 5 times.
Pd-sepiolite catalyst for Suzuki coupling reaction in water: Structural and catalytic investigations
Shimizu, Ken-Ichi,Maruyama, Rei,Komai, Shin-Ichi,Kodama, Tatsuya,Kitayama, Yoshie
, p. 202 - 209 (2004)
[Pd(NH3)4]2+-exchanged sepiolite clay (Pd-sepiolite) has been applied to the catalytic Suzuki-type carbon-carbon coupling reactions of 4-bromophenol with phenylboronic acid or sodium tetraphenylborate in water. The Pd-sepiolite effectively catalyzed the reaction under mild reaction conditions (at room temperature in air). The Pd-sepiolite system exhibits higher yield than unsupported Pd(II) salts, [Pd(NH 3)4]Cl2-impregnated SiO2 (Pd-SiO2), and a commercially available Pd/C consisting of Pd metal particles. The structure of Pd species in the catalysts before and after the reaction was well characterized by a combination of XRD, TEM, UV-Vis, Pd K-edge XANES/EXAFS, and Pd LIII-edge XANES. XAFS and TEM results confirmed the formation of metal particles after the reaction by unsupported Pd(II) salt and Pd-SiO2. In contrast, for Pd-sepiolite the change in the structure of Pd species after the reaction was not significant; the highly dispersed Pd(II) complex, present before the reaction, was still the main Pd species together with the small Pd clusters (2-7 nm) as minor species. As a result of the high stability, Pd-sepiolite was reused without losing its activity. Significantly high turnover numbers (TON=940,000) were also attained at reflux temperature. It is suggested that Pd metal precipitation during the reaction is inhibited by a strong electrostatic interaction of sepiolite with Pd(II) species.
Chitosan as a support for heterogeneous Pd catalysts in liquid phase catalysis
Leonhardt, Silke E.S.,Stolle, Achim,Ondruschka, Bernd,Cravotto, Giancarlo,Leo, Cristina De,Jandt, Klaus D.,Keller, Thomas F.
, p. 30 - 37 (2010)
Four different chitosan-supported palladium catalysts were prepared, whereby two of them were modified as Schiff base by reaction with salicylaldehyde and 2-pyridinecarboxaldehyde before complexation with palladium. The remaining differ in their preparation method: co-precipitation or adsorption. The properties of the catalysts were characterized by FTIR, XPS, ICP-MS, and TGA. Comparison of the catalysts activity was assessed in microwave-assisted Suzuki reactions in aqueous media, resulting in good yields and excellent selectivities concerning cross-coupling product. Additionally, the catalysts prove their activity under conductive heating conditions. The study was extended to microwave-assisted Heck and Sonogashira reactions in DMF, confirming the efficiency of chitosan-supported palladium derivatives as catalysts for C-C couplings. Experiments revealed that catalysts prepared by co-precipitation furnished inferior yields concerning the employed C-C coupling reactions. Modification of chitosan with 2-pyridinecarboxaldehyde and subsequent palladium deposition resulted in highly active catalysts affording high product selectivities and yields.
