1694-19-5Relevant academic research and scientific papers
Synthesis of magnetically recyclable Fe3O4@[(EtO)3Si–L1H]/Pd(II) nanocatalyst and application in Suzuki and Heck coupling reactions
Keypour, Hassan,Saremi, Shokoufeh Ghahri,Noroozi, Mohammad,Veisi, Hojat
, (2017)
A Pd(II) Schiff base complex as an efficient and highly heterogeneous catalyst was developed by immobilization of a palladium complex on the surface of modified Fe3O4 magnetite nanoparticles. These surface-modified nanoparticles were characterized using various techniques such as transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, elemental analysis and Fourier transform infrared spectroscopy. The palladium catalyst exhibited efficient catalytic activity in Suzuki and Heck coupling reactions. This method has notable advantages such as excellent chemoselectivity, mild reaction conditions, short reaction times and excellent yields. The yields of the products were in the range 85–100%. Also, the nanocatalyst can be easily recovered with a permanent magnet and reused at least five times without noticeable leaching or loss of its catalytic activity. Copyright
New poly-imidazolium-triazole particles by CuAAC cross-linking of calix[4]arene bis-azide/alkyne amphiphiles - a prospective support for Pd in the Mizoroki-Heck reaction
Burilov, Vladimir,Garipova, Ramilya,Mironova, Diana,Sultanova, Elza,Bogdanov, Ilshat,Ocherednyuk, Evgeny,Evtugyn, Vladimir,Osin, Yuri,Rizvanov, Ildar,Solovieva, Svetlana,Antipin, Igor
, p. 584 - 591 (2020)
A new imidazolium amphiphilic calix[4]arene with terminal acetylene fragments in the polar region was synthesized according to a two step scheme including regioselective chloromethylation of distal di-O-butyl calix[4]arene and subsequent interaction with 1-(hex-5-yn-1-yl)-1H-imidazole. The aggregation properties (CAC, the size and zeta potential of aggregates) of alkynyl calix[4]arene as well as of previously synthesized azidopropyl calix[4]arene and their 1?:?1 mixture were disclosed. Macrocycles with azide and alkyne fragments in the polar region were covalently cross-linked under CuAAC conditions in water. Successful cross-linking of molecules has been proven by IR spectroscopy and MALDI-TOF spectrometry. The obtained polymeric particles were studied both in solution and the solid state and the presence of submicron (～200 nm) and micron (～1-5 μm) particles with the prevalence of the latter was found. The average molecular weight of the polymer according to the static light scattering data was found to be 639 ± 44 kDa. The obtained polymeric imidazolium-triazole particles were tested as a support for Pd(OAc)2in the Mizoroki-Heck reaction carried out in both organic and water media. In both solvents (especially in water) the addition of imidazolium-triazole particles to Pd(OAc)2increased the conversion of 4-iodanisole. It was found that the ratio between the products (1,1 and 1,2-substituted ethylenes) changes drastically on going from DMF to water from 1?:?5 to 1?:?40 when using supported Pd(OAc)2
Continuous-flow Heck synthesis of 4-methoxybiphenyl and methyl 4-methoxycinnamate in supercritical carbon dioxide expanded solvent solutions
Lau, Phei Li,Allen, Ray W. K.,Styring, Peter
, p. 2886 - 2897 (2013)
The palladium metal catalysed Heck reaction of 4-iodoanisole with styrene or methyl acrylate has been studied in a continuous plug flow reactor (PFR) using supercritical carbon dioxide (scCO2) as the solvent, with THF and methanol as modifiers.
Hydrogel supported vinylimidazole based PEPPSI-Pd-NHC catalysts: The catalytic activities in Heck and Suzuki-Miyaura coupling reactions
Boztepe, Cihangir,Künkül, As?m,Gürbüz, Nevin
, (2020)
Increasing environmental awareness and limited raw material resources have increased the importance of catalysts by leading to green technology. For this purpose, there is a need for efficient, new, selective, reusable, environmentally friendly catalysts
Stereoselective Base-Catalyzed 1,1-Silaboration of Terminal Alkynes
Gu, Yiting,Duan, Yaya,Shen, Yangyang,Martin, Ruben
, p. 2061 - 2065 (2020)
A base-catalyzed reaction that enables stereoselective 1,1-silaboration of terminal alkynes is described. This method not only offers a new strategy to functionalize simple and readily accessible alkynes beyond 1,2-difunctionalization, but also provides a
PEG-modified N-heterocyclic carbene ligands for highly efficient and recyclable Pd-catalyzed Heck reaction in water
Liu, Yulan,Wang, Yan,Long, Ensheng
, p. 11 - 15 (2014)
A water-soluble and air-stable Pd(OAc)2/mPEG n MeImI system was found to be a highly efficient and reusable catalyst for the coupling of aryl halides and styrene in neat water using K2CO3 as base. After extraction, the catalytic system could be reused several times with only a slight decrease in its activity.
New fragmentation and rearrangement reactions of the azetidine ring promoted by AlEt2Cl
Alcaide, Benito,Salgado, Nati R.,Sierra, Miguel A.
, p. 467 - 470 (1998)
Azetidines 6 prepared by AlH2Cl reduction of easily available β-lactams 5 react with AlEt2Cl in CH2Cl2 solution at room temperature to yield, through new fragmentation or rearrangement reactions of the azetidine ring, either, olefins 7 or bicyclic fused pyrrolidines 8, depending on the nature of the group bonded to C2 of the four membered ring.
Synthesis, crystal structures, magnetic properties and Suzuki and Heck coupling catalytic activities of new coordination polymers containing tetracyanopalladate(II) anions
?enocak, Ay?egül,Karada?, Ahmet,Yerli, Yusuf,Gürbüz, Nevin,?zdemir, Ismail,?ahin, Ertan
, p. 50 - 60 (2013)
Four novel coordination polymers, [Ni(bishydeten)Pd(CN)4] (1), [Cu(bishydeten)Pd(CN)4] (2), [Zn(bishydeten)Pd(CN)4] (3) and [Cd(bishydeten)Pd(CN)4] (4) (bishydeten = N,N′-bis(2- hydroxyethyl)ethylenediamine], have been synthesized and characterized by various techniques (elemental analysis, IR, EPR, X-ray and thermal analysis). In compound 4, all of the cyano groups use -N edges to form coordination bonds to Cd(II) in addition to -C atoms, resulting in the formation of a tridimensional network. The same situation is observed for compound 3 for one of the tetracyanopalladate(II) groups, while two cyano groups remain in the monodentate form coordinated to Pd(II) in the other tetracyanopalladate(II) group. While an EPR signal was not observed for 1, the g parameters obtained from the EPR spectrum of 2 indicated that the Cu(II) ions are located in tetragonal distorted octahedral sites (D4h) and that the ground state of the paramagnetic electron is dx2-y2. Variable temperature magnetic susceptibility measurements recorded in the range 15-300 K showed the presence of a very small antiferromagnetic interaction below 20 K for complexes 1 and 2. 2 was proven to be less effective as a catalyst than 1 under the Heck reaction conditions. Moreover, 1 was determined to be a more effective catalyst and more efficient for iodoarenes than bromoarenes under Suzuki coupling conditions.
[60]Fullerene-Based Pd(0) Complexes of Phosphorus Ylides as Efficient Nanocatalyst for Homo- and Heterogeneous Mizoroki–Heck Coupling Reactions
Sabounchei, Seyyed Javad,Hashemi, Ali,Hosseinzadeh, Marjan,Salehzadeh, Sadegh,Maleki, Farahnaz
, p. 2319 - 2331 (2017)
Abstract: This work reports the synthesis and catalytic properties of new mono- and bidentate palladium(0)-[60]fullerene complexes, prepared by reaction of α-keto stabilized phosphorus ylides [Ph2P(CH2)nPPh2=C(H)C(O)C6H4-p-R] (n = 1, R = Ph, NO2, (Y1, Y2); n = 2, R = Ph, NO2, (Y3, Y4)), C60 and Pd(dba)2 (dibenzylideneacetone (dba)). Two coordination modes were observed: bidentate P,C-coordinated in the case of [(η ?C60)Pd(κ2 ?Y1)] (1) and [(η2?C60)Pd(κ2?Y2)] (2) and monodentate P-coordinated for [(η2?C60)Pd(Y3)2] (3) and [(η2?C60)Pd(Y4)2] (4) complexes. All complexes have been fully characterized by 1H, 13C and 31P NMR spectroscopic methods and other conventional techniques such as IR, thermogravimetry, inductively coupled plasma optical emission spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and transmission electron microscopy analysis. Also, the catalytic activity of [60]fullerene-based nanocatalyst 2 in homo- and heterogeneous Mizoroki–Heck coupling reactions of various aryl chlorides with styrene was evaluated. The results implied that the both reactions exhibit their beneficial aspects such as high activity for homogeneous catalysis and facile separation and reusability for heterogeneous one. Furthermore, DFT studies of geometry-optimized monodentate and bidentate structures for 1 and 3 were calculated at the BP86/LANL2DZ and B3LYP/LANL2MB levels of theory to understand the origin of the observed coordination modes. Graphical Abstract: [Figure not available: see fulltext.].
A macrocyclic Pd(II)-Ni(II) complex in Heck and Suzuki reactions
Mieczyńska, Ewa,Lisowski, Jerzy,Trzeciak, Anna M.
, p. 145 - 149 (2015)
A heterodinuclear Pd(II)-Ni(II) macrocyclic Schiff base complex was applied as a catalyst for Heck and Suzuki cross-coupling reactions. In reaction of 4-bromoanisole with styrene, 4-methoxy-trans-stilbene was formed as the main product with a yield of up to 87%. In the Suzuki coupling of 4-bromoanisole with PhB(OH)2in a 2-propanol/water solution, up to 96% of the product was obtained. Analyses of the post-reaction mixtures confirmed the high stability of the macrocyclic Pd(II)-Ni(II) complex under the reaction conditions. The partial decomposition of the complex started at the Ni(II) site.
