3218-36-8Relevant articles and documents
Highly efficient polymer-based nanoreactors for selective oxidation of alcohols in water
Chen, Tao,Xu, Zhenkai,Zhou, Lei,Qiu, Jiaqi,Wang, Maolin,Wang, Jiping
, (2019)
In this study, we demonstrate the fabrication of thermo-responsive polymer-based TEMPO nanoreactors and their application in the catalytic selective oxidation of alcohols as a highly efficient and recoverable catalyst in aqueous media. First, a diblock amphiphilic copolymer NHS-P(MMA25-b-OEGMA75) consisting of poly(methyl methacrylate) (PMMA) and poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA300) with a terminal N-hydroxysuccinimide (NHS) activated ester was synthesized utilizing reversible addition–fragmentation chain transfer polymerization (RAFT) techniques. Free radical 2,2,6,6,-tetramethyipiperidinooxy (TEMPO) was then introduced into the end of the copolymer based on activated ester functionalization to afford the temperature responsive polymer-supported catalyst TEMPO-P(MMA25-b-OEGMA75). Next, core-shell TEMPO nanoreactors were formed through self-assembly of the amphiphilic block polymers in deionized water. The morphology of the nanoreactors was well characterized by dynamic light scattering (DLS) and scanning electron microscopy (SEM). The nanoreactors were then successfully applied in the selective oxidative of alcohols in water. A variety of aldehydes and ketones were achieved in excellent yields and selectivities in high reaction rates with low catalyst loading. The high efficiency in catalysis of the nanoreactors may attributed to the ideal environment where enhancing the interactions between the catalyst and the alcohol substrate, mimicking the environment of enzymes. The thermo-responsive polymer-based nanoreactors could be conveniently recovered in the temperature above the LCST of the polymer after extraction of product from the reaction mixture. This strategy provides an effective and cleaner way for the selective oxidative of alcohols in organic synthesis and industrial application.
Azo-azomethine based palladium(II) complexes as catalysts for the Suzuki-Miyaura cross-coupling reaction
Da?, Ay?e Kazanc?,Evren, Enes,Gürbüz, Nevin,Ikiz, Mesut,Inan, Ay?e,Ispir, Esin,K?se, Muhammet,Ozdemir, ?smail,Sünbül, Ali Burak
, (2020)
Seven azo-azomethine ligands (2-8) have been synthesized from the reaction of (E)-5-((4-chlorophenyl)diazenyl)-2-hydroxybenzaldehyde with different aniline derivatives. Ligand structures were characterized by the combination of IR, UV–Visible spectroscopy
Synthesis, characterization and theoretical and fluorescence emission microscopy studies of new Pd/Pt–cyclopropa[60]fullerene complexes: Application of Taguchi method for optimization of parameters in Suzuki–Miyaura reaction
Sabounchei, Seyyed Javad,Badpa, Khadijeh,Hashemi, Ali,Salehzadeh, Sadegh,Maleki, Farahnaz,Hosseinzadeh, Leila
, (2018)
The reactions of unsymmetric phosphorus ylides of the type [Ph2P(CH2)nPPh2?C(H)C(O)C6H4-p-CN] (n?=?1 (Y1); n?=?2 (Y2)) with C60 and M(dba)2 (M?=?Pd or Pt; dba?=?dibenzylideneacetone) are reported. Based on the various coordination modes of these ylides in complexation, the following new Pd/Pt–cyclopropa[60]fullerene complexes were obtained: P,C-coordinated [(η2-C60)Pd(κ2-Y1)] (1) and [(η2-C60)Pt(κ2-Y1)] (2) complexes and P-coordinated [(η2-C60)Pd(Y2)2] (3) and [(η2-C60)Pt(Y2)2] (4) complexes. These compounds were characterized using Fourier transform infrared, UV–visible and NMR (1H, 13C and 31P) spectroscopies and scanning electron microscopy. Furthermore, cytotoxicity studies showed that nanoparticles of these complexes can be used as non-toxic labels for cellular imaging application. Also energy decomposition analysis results revealed that the percentage contribution of ΔEelec in total interaction energy is considerably larger than that of ΔEorb. Thus, in all complexes the (η2-C60)M?(Y1) bond is considerably more electrostatic in nature than the (η2-C60)?M(Y1) bond. Finally, by application of the Taguchi method for optimization of parameters in Suzuki–Miyaura reaction, the catalytic activity of Pd complexes 1 and 3 was investigated in the cross-coupling reaction of various aryl chlorides with phenylboronic acid. According to analysis of variance results, solvent has the highest F value and it has high contribution percentage (36.75%) to the yield of Suzuki–Miyaura reaction.
Fluoride-triggered indium-mediated synthesis of (hetero)biaryls
Font-Sanchis, Enrique,Sastre-Santos, Angela,Fernandez-Lazaro, Fernando
, p. 2470 - 2473 (2009)
A simple method for the preparation of triorganoindium reagents under mild conditions based in indium-silicon exchange is described.
Palladium(II) catalyzed Suzuki C–C coupling reactions with imino- and amino-phosphine ligands
Kemal Y?lmaz, Mustafa,?nce, Simay,Y?lmaz, Sevilay,Kele?, Mustafa
, p. 252 - 258 (2018)
A new series of bidentate PN type imino- (1–3) and amino-phosphine ligands (4–6) and their palladium(II) complexes [Pd(PN)Cl2] (1a–6a) have been synthesized and fully characterized using spectroscopic and analytical methods, including 31P, 1H, 13C NMR and FTIR spectroscopy and high resolution mass spectroscopy. The catalytic activities of the Pd(II) complexes were investigated for the Suzuki C–C coupling reactions of phenylboronic acid with aryl bromides using a substrate to catalyst ratio of 500/1. The effect of base, temperature and solvent has been investigated, and the highest reaction rates were observed at 80 °C in dimethylformamide (DMF) with K2CO3 as the base in 12 h. Under optimized reaction conditions, generally higher coupled product was obtained with substituted aryl bromides, including both electron-withdrawing (-formyl and -aceto) or -donating groups (-methyl and -methoxy) at -ortho or -para positions, except 2-bromoacetophenone which has bulkier -aceto group compared to the other aryl bromides.
Polymer supported palladium complex as a reusable catalyst for Suzuki coupling
Renuka,Gayathri
, p. 26 - 31 (2018)
Novel, simple and efficient catalytic system based on a polymer supported Pd complex of 2,6-bis(benzimidazolyl)pyridine, Pd(PS–BBP)Cl2, was found to be highly active for Suzuki–Miyaura cross-coupling of aryl halides with phenylboronic acids under mild conditions. The catalyst was characterized by CHN analyses, thermogravimetric analyses, BET surface area measurements, ICP-OES, FT-IR and electronic spectral studies. The effect of solvent, base, temperature and catalyst concentration on the coupling reaction of iodobenzene with phenylboronic acid was also investigated. A variety of functional groups are tolerated. The novel catalyst could be recovered in a facile manner from the reaction mixture and could be reused up to seven times without significant loss of catalytic activity.
Nitrogen-rich porous covalent imine network (CIN) material as an efficient catalytic support for C-C coupling reactions
Bhunia, Manas K.,Das, Swapan K.,Pachfule, Pradip,Banerjee, Rahul,Bhaumik, Asim
, p. 1304 - 1311 (2012)
In an effort to expand the realm of possibilities of nitrogen-rich porous materials that could be used in catalysis, herein we report the synthesis of a new highly nitrogen rich (ca. 45%) porous covalent imine network (CIN-1) material employing simple Schiff base chemistry and further grafting its surface with palladium. Pd-loaded CIN-1 support acts as a truly heterogeneous catalyst towards Suzuki C-C coupling reaction between aryl halides with arylboronic acids. High surface area and excellent accessibility of the catalytic sites make it very efficient for heterogeneous catalysis. The stability of the catalyst due to intimate contact between nitrogen-rich organic support and metal allows several reuses with only a minor loss in catalytic activity.
Pd nanoparticles embedded in mesoporous carbon: A highly efficient catalyst for Suzuki-Miyaura reaction
Zhong, Lin,Chokkalingam, Anand,Cha, Wang S.,Lakhi, Kripal S.,Su, Xiangyang,Lawrence, Geoffrey,Vinu, Ajayan
, p. 195 - 198 (2015)
Mesoporous carbon functionalized with Pd nanoparticles (Pd@MC) was synthesized via one-pot method using SBA-15, furfuryl alcohol and PdCl2 as a template, a carbon source and a palladium source, respectively. The HRTEM image shows that Pd nanoparticles are homogeneously distributed on the surface of nanoporous carbon whereas the XPS spectrum of the catalyst indicates that Pd exists in the form of Pd (0). With a low loading of the catalyst (2 mol% Pd), Pd@MC shows a high conversion (100%) and selectivity for the desired product (>95%) in the Suzuki-Miyaura reactions of acyl halides with phenylboronic acid under a mild reaction condition. The catalyst was found to be highly active and no leaching in the reaction is observed. The catalyst can further be recycled for up to three times without loss of reactivity.
Synthesis and characterization of a supported Pd complex on volcanic pumice laminates textured by cellulose for facilitating Suzuki-Miyaura cross-coupling reactions
Soltani, Siavash Salek,Taheri-Ledari, Reza,Farnia, S. Morteza F.,Maleki, Ali,Foroumadi, Alireza
, p. 23359 - 23371 (2020)
Herein, a novel high-performance heterogeneous catalytic system made of volcanic pumice magnetic particles (VPMP), cellulose (CLS) natural polymeric texture, and palladium nanoparticles (Pd NPs) is presented. The introduced VPMP@CLS-Pd composite has been designed based on the principles of green chemistry, and suitably applied in the Suzuki-Miyaura cross-coupling reactions, as an efficient heterogeneous catalytic system. Concisely, the inherent magnetic property of VPMP (30 emu g-1) provides a great possibility for separation of the catalyst particles from the reaction mixture with great ease. In addition, high heterogeneity and high structural stability are obtained by this composition resulting in remarkable recyclability (ten times successive use). As the main catalytic sites, palladium nanoparticles (Pd NPs) are finely distributed onto the VPMP@CLS structure. To catalyze the Suzuki-Miyaura cross-coupling reactions producing biphenyl pharmaceutical derivatives, the present Pd NPs were reduced from chemical state Pd2+ to Pd0. In this regard, a plausible mechanism is submitted in the context as well. As the main result of the performed analytical methods (including FT-IR, EDX, VSM, TGA, FESEM, TEM, BTE, and XPS), it is shown that the spherical-shaped nanoscale Pd particles have been well distributed onto the surfaces of the porous laminate-shaped VPMP. However, the novel designed VPMP@CLS-Pd catalyst is used for facilitating the synthetic reactions of biphenyls, and high reaction yields (～98percent) are obtained in a short reaction time (10 min) by using a small amount of catalytic system (0.01 g), under mild conditions (room temperature).
Palladium-catalyzed Suzuki-Miyaura reaction of aryl chlorides in aqueous media using tetrahydrodiazepinium salts as carbene ligands
?zdemir, Ismail,Gürbüz, Nevin,G?k, Yetkin,?etinkaya, Engin,?etinkaya, Bekir
, p. 2394 - 2396 (2005)
A highly effective, easy to handle, and environmentally benign process for palladium-mediated Suzuki cross-coupling was developed. The in situ prepared three-component system of Pd(OAc)2, 1,3-dialkyltetrahydrodiazepinium chlorides (2a-e), and K
