82989-26-2Relevant academic research and scientific papers
Palladium Nanoparticles Anchored on Magnesium Organosilicate: An Effective and Selective Catalyst for the Heck Reaction
Dos Santos, Beatriz F.,Da Silva, Beatriz A. L.,De Oliveira, Aline R.,Sarragiotto, Maria H.,Rinaldi, Andrelson W.,Domingues, Nelson Luís C.
supporting information, p. 1301 - 1306 (2020/11/04)
A new and effective palladium catalyst supported on a magnesium organosilicate for application in the Heck reaction is presented. A group of compounds comprising 22 examples were synthesized in moderate to high yields (up to 99%) within a short time. The palladium supported on magnesium organosilicate catalyst was characterized as an amorphous solid by SEM, containing around 33% of palladium inside the solid, and even with this low quantity of palladium, the catalyst was very efficient in the Heck reaction. Besides, based on the Scherrer equation, the crystallite size of the synthesized palladium nanoparticles was ultrasmall (around 1.3 nm). This strategy is a simple and efficient route for the formation of C-C bonds via the Heck cross-coupling reaction.
Extended architectures constructed of thiourea-modified SBA-15 nanoreactor: A versatile new support for the fabrication of palladium pre-catalyst
Alamgholiloo, Hassan,Noroozi Pesyan, Nader,Rostamnia, Sadegh
, (2020/02/04)
We designed and synthesized a novel catalyst consisting of ordered mesoporous silica (SBA-15) functionalized with bis(thiourea) (BTU) linker. The regular and unique pore channels of BTU-SBA-15 ensure proper control of the size and homogeneous distribution of palladium nanoparticles. The physiochemical properties of the hybrid Pd?BTU-SBA-15 pre-catalyst were investigated using various techniques. The proposed catalyst is found to be very active, reusable, stable and scalable, and has excellent reactivity and selectivity for Suzuki and Heck coupling reactions under very mild and sustainable reaction conditions.
Gold-catalyzed partial hydrogenation of activated alkynes mediated by triphenylphosphine
Cocoletzi-Xochitiotzi, Ana Patricia,Hernández-Hernández, Miguel,Medina-Mercado, Ignacio,Jiménez-Martínez, Williams De Jesús,Mastranzo, Virginia Maricela,Porcel, Susana
, p. 2379 - 2386 (2020/08/19)
Gold(I) can exhibit a cooperative effect with triphenylphosphine, accelerating the triphenylphosphine-mediated partial hydrogenation of activated alkynes. In this protocol, 3-arylpropiolates are selectively reduced to the Z -isomer when the aryl ring bears an electron-donor substituent, whereas 3-arylpropynones are reduced to the E-isomers.
Mizoroki–Heck cross-coupling reactions using palladium immobilized on DABCO-functionalized silica
Jadhav, Sanjay,Patil, Seema,Kumbhar, Arjun,Kamble, Santosh,Salunkhe, Rajashri
, p. 507 - 514 (2019/04/25)
A heterogeneous palladium catalyst supported on silica modified by DABCO has been prepared by post-synthetic modification of silica gel. This heterogeneous catalytic system exhibits high activity and stability in the Mizoroki–Heck cross-coupling reaction of various aryl halides with olefins. The reaction proceeds efficiently under efficiently under mild mild reaction conditions and high yield, with the formation of E-isomers selectively. Moreover, we successfully established a gram-scale synthesis, and the catalyst was reused for up to ten catalytic cycles.
Monodentate phosphorus-coordinated palladium(II) complexes as new catalyst for Mizoroki-Heck reaction of aryl halides with electron-deficient olefins
Zhao, Fang,Xin, Li,Zhang, Yingying,Jia, Xuefeng
supporting information, p. 493 - 496 (2017/09/06)
Four novel palladium(II) complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H-1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki-Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of aryl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd(OAc)2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis
Stepwise post-modification immobilization of palladium Schiff-base complex on to the OMS-Cu (BDC) metal–organic framework for Mizoroki-Heck cross-coupling reaction
Alamgholiloo, Hassan,Rostamnia, Sadegh,Hassankhani, Asadollah,Khalafy, Jabbar,Baradarani, Mehdi M.,Mahmoudi, Ghodrat,Liu, Xiao
, (2018/09/06)
Palladium ions were successfully immobilized within the pores of open metal site (OMS) metal organic frameworks (MOFs) with Schiff-base (2-Py-SI) grafted in OMS-Cu (BDC) using the hydrothermal method. This Schiff-base complex on the Cu (BDC) greatly increased catalytic activity and acted as an efficient stabilizer of Pd ions. The hydrothermal method was a more efficient method for generating small metal ions in the MOF structures. The results revealed that the PdII@Cu (BDC)/2-Py-SI is a promising catalyst for the Mizoroki-Heck coupling reaction. The proposed catalyst has better recyclability and can be reused several times without apparent loss of activity.
Dual Ligand-Enabled Nondirected C?H Olefination of Arenes
Chen, Hao,Wedi, Philipp,Meyer, Tim,Tavakoli, Ghazal,van Gemmeren, Manuel
supporting information, p. 2497 - 2501 (2018/02/06)
The application of the Pd-catalyzed oxidative C?H olefination of arenes, also known as the Fujiwara–Moritani reaction, has traditionally been limited by the requirement for directing groups on the substrate or the need to use the arene in large excess, ty
Silica-coated nano-Fe3O4-supported iminopyridine palladium complex as an active, phosphine-free and magnetically separable catalyst for Heck reactions
Zhang, Qiang,Zhao, Xin,Wei, Huai-Xin,Li, Ji-Hang,Luo, Jun
, (2017/04/21)
A novel magnetic nanoparticle-supported iminopyridine palladium complex was successfully prepared by attaching palladium acetate to iminopyridine ligand-functionalized silica-coated nano-Fe3O4. The as-prepared catalyst was well characterized and was evaluated in Heck reactions in terms of activity and recyclability. It was found to be highly efficient for the reactions of various aryl iodides and aryl bromides having electron-withdrawing groups with olefins under phosphine-free and inert atmosphere-free conditions. Moreover, the catalyst could be conveniently recovered using an external magnet, and the recyclability was influenced by the base in the Heck reaction. The catalyst could be reused at least six times with no significant loss in activity when triethylamine acted as the base.
An efficient palladium catalyzed Mizoroki-Heck cross-coupling in water
Jadhav, Sanjay N.,Rode, Chandrashekhar V.
supporting information, p. 5958 - 5970 (2017/12/26)
The homogeneous Pd-catalysed Mizoroki-Heck coupling reaction was successfully performed in water in the absence of any additives under aerobic conditions. The various key reaction parameters that affect the yield of the desired cross-coupling product were optimized. The Pd(PPh3)4/Et3N/H2O/98 °C catalyst system was found to be highly active (TOF = 12 to 14 h-1) towards achieving excellent yield of the Mizoroki-Heck coupling products for a wide range of electron-withdrawing as well as electron-donating aryl bromides and chlorides in the shortest reaction time. Pd(PPh3)4 catalyst deactivation during the Mizoroki-Heck coupling reaction was investigated and to evolve a strategy for achieving ten times Pd-metal recyclability without appreciable loss of its activity. Thus, the proposed mechanism provides access to a variety of olefins in aqueous medium, making this protocol eco-friendly.
New pallada- and platinacycle complexes of phosphorus ylide: Synthesis, structural characterization, antioxidant capacity and catalytic behavior towards Mizoroki-Heck reactions
Javad Sabounchei, Seyyed,Hashemi, Ali,Yousefi, Abed,Gohari Derakhshandeh, Parviz,Karamian, Roya,Asadbegy, Mostafa,Van Hecke, Kristof
, p. 1 - 9 (2017/07/22)
The reactions of α-keto stabilized phosphorus ylide Ph2P(CH2)2PPh2C(H)C(O)C6H4-m-Br (Y) with [MCl2(cod)] (M?=?Pd or Pt; cod?=?1,5-cyclooctadiene) in equimolar ratio using dichloromethane as a solvent are reported. These reactions led to the formation of new P, C-chelated pallada- and platinacycle complexes [MCl2(Ph2P(CH2)2PPh2C(H)C(O)C6H4-m-Br)] (M?=?Pd (C1) and Pt (C2)). Characterization of the obtained compounds was performed by elemental analysis and IR, 1H, 13C, and 31P NMR spectroscopic methods. Also, the unequivocal structures of these complexes were characterized crystallographically. Both structures consist of six-membered rings formed by coordination of the phosphorus ylide (Y) through the phosphine group and the ylidic carbon atom to the metal center. Furthermore, palladacycle C1 was employed as an efficient catalyst in the Mizoroki-Heck coupling reaction of several aryl chlorides and olefins. The coupled products of these reactions were obtained under aerobic conditions in high yields using aqueous DMF as a solvent. Additionally, the antioxidant capacity of the reported compounds with butylated hydroxytoluene (BHT) as standard was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. Apparently, all synthesized compounds possess strong antioxidant capacity (IC50; 0.584?±?0.009–0.751?±?0.003?mg/ml).
