125951-00-0Relevant articles and documents
Highly active Pd(II) catalysts with trans-bidentate pyridine ligands for the Heck reaction
Kawano, Tomikazu,Shinomaru, Tatsuji,Ueda, Ikuo
, p. 2545 - 2547 (2002)
(Matrix presented) The air-, water-, and heat-stable palladium(II) complexes 2a and 2b are prepared by the reaction of palladium(II) salts with the new transbidentate nitrogen ligands, 1,2-bis(2-pyridylethynyl)benzenes. The structure of complex 2a has bee
Integrated Process of Aerobic Oxidation-Olefination-Asymmetric C-C Bond Formation Catalyzed by Robust Heterogeneous Gold/Palladium and Chirally Modified Rhodium Nanoparticles
Miyamura, Hiroyuki,Suzuki, Aya,Yasukawa, Tomohiro,Kobayashi, Shu
, p. 3815 - 3819 (2015)
We have achieved an integrated process of oxidation-olefination-asymmetric 1,4-addition reactions under aerobic and aqueous conditions using metal nanoparticles as robust heterogeneous catalysts. A tandem process of aerobic oxidation and Horner-Wadsworth-Emmons olefination was successfully catalyzed by gold/palladium bimetallic nanoparticles. A wide range of substrates gave the desired products in high yields and excellent selectivities. This tandem process was further connected with an asymmetric 1,4-addition reaction catalyzed by chiral rhodium nanoparticles to achieve a challenging three-step, one-pot sequential reaction. Various types of esters with a chiral center at the β-position were obtained from readily available and stable alcohols and arylboronic acids in high yields with high enantioselectivities in a one-pot sequential reaction integrating three transformations.
An efficient synthesis of 2-arylimidazoles by oxidation of 2-arylimidazolines using activated carbon-O2 system and its application to palladium-catalyzed Mizoroki-Heck reaction
Haneda, Satoshi,Okui, Ayaka,Ueba, Chigusa,Hayashi, Masahiko
, p. 2414 - 2417 (2007)
Oxidative conversion of 2-substituted imidazoline (dihydroimidazole) to the corresponding imidazole was achieved by an activated carbon-O2 system. Also, the 2-arylimidazolines and 2-arylimidazoles have been found to work as simple ligands in the palladium-catalyzed Mizoroki-Heck reaction.
Mizoroki-Heck and Sonogashira cross-couplings catalyzed by CNC palladium pincer complexes in organic and aqueous media
SanMartin, Raul,Ines, Blanca,Moure, Maria Jesus,Herrero, Maria Teresa,Dominguez, Esther
, p. 955 - 962 (2012)
The catalytic activity of two CNC palladium pincer complexes is evaluated in two fundamental C - C bond-forming reactions: Mizoroki - Heck and Sonogashira cross-couplings. After several optimization attempts and a brief comparison with a PCN pincer cataly
Imidazole and imidazoline derivatives as N-donor ligands for palladium-catalyzed Mizoroki-Heck reaction
Haneda, Satoshi,Ueba, Chigusa,Eda, Kazuo,Hayashi, Masahiko
, p. 833 - 835 (2007)
Imidazole and imidazoline (dihydroimidazole) derivatives can serve as efficient and simple Iigands for the palladium-catalyzed Mizoroki-Heck reaction. Among the imidazole and imidazoline derivatives in our investigations, the 2-methylimidazoline-palladium
N-Heterocyclic carbene palladium (II)-pyridine (NHC-Pd (II)-Py) complex catalyzed heck reactions
Li, Dan,Tian, Qingqiang,Wang, Xuetong,Wang, Qiang,Wang, Yin,Liao, Siwei,Xu, Ping,Huang, Xin,Yuan, Jianyong
supporting information, p. 2041 - 2052 (2021/05/25)
A mild, efficient, and practical catalytic system for the synthesis of highly privileged stilbene pharmacophores is reported. This system uses N-heterocyclic carbene palladium (II) Pyridine (NHC-Pd (II)-Py) complex to catalyze the formation of carbon-carbon bonds between olefin derivatives and various bromide. This simple, gentle and user-friendly method can offer a variety of stilbene products in excellent yields under solvent-free condition. And its scale-up reaction has excellent yield and this system can be applied to industrial fields. The utility of this method is highlighted by its universality and modular synthesis of a series of bioactive molecules or important medical intermediates.
Non-Chelate-Assisted Palladium-Catalyzed Aerobic Oxidative Heck Reaction of Fluorobenzenes and Other Arenes: When Does the C?H Activation Need Help?
Albéniz, Ana C.,Villalba, Francisco
supporting information, p. 4795 - 4804 (2021/09/06)
The pyridone fragment in the ligand [2, 2’-bipyridin]-6(1H)-one (bipy-6-OH) enables the oxidative Heck reaction of simple arenes with oxygen as the sole oxidant and no redox mediator. Arenes with either electron-donating or electron-withdrawing groups can be functionalized in this way. Experimental data on the reaction with toluene as the model arene shows that the C?H activation step is turnover limiting and that the ligand structure is crucial to facilitate the reaction, which supports the involvement of the pyridone fragment in the C?H activation step. In the case of fluoroarenes, the alkenylation of mono and 1,2-difluoro benzenes requires the presence of bipy-6-OH. In contrast, this ligand is detrimental for the alkenylation of 1,3-difluoro, tri, tetra and pentafluoro benzenes which can be carried out using just [Pd(OAc)2]. This correlates with the acidity of the fluoroarenes, the most acidic undergoing easier C?H activation so other steps of the reaction such as the coordination-insertion of the olefin become kinetically important for polyfluorinated arenes. The use of just a catalytic amount of sodium molybdate as a base proved to be optimal in all these reactions. (Figure presented.).
Gelatin-pyrolyzed mesoporous N-doped carbon supported Pd as high-performance catalysts for aqueous Heck reactions
Yang, Shuai,Chen, Yuli,Huang, Shuaijian,Deng, Lu,Wu, Yuanyuan,Zheng, Xiu,Omonov, Shakhzodjon,Zeng, Minfeng
, (2021/05/19)
Nitrogen-doped mesoporous carbon-supported Pd (Pd@N-C) catalysts were prepared by pyrolyzing gelatin/templates/PdCl2 hydrogels under N2 atmosphere at 800°C. Using poly (ethylene glycol) block poly (propylene glycol) block poly (ethyl
Selective Construction of C?C and C=C Bonds by Manganese Catalyzed Coupling of Alcohols with Phosphorus Ylides
Liu, Xin,Werner, Thomas
supporting information, p. 1096 - 1104 (2020/12/31)
Herein, we report the manganese catalyzed coupling of alcohols with phosphorus ylides. The selectivity in the coupling of primary alcohols with phosphorus ylides to form carbon-carbon single (C?C) and carbon-carbon double (C=C) bonds can be controlled by the ligands. In the conversion of more challenging secondary alcohols with phosphorus ylides the selectivity towards the formation of C?C vs. C=C bonds can be controlled by the reaction conditions, namely the amount of base. The scope and limitations of the coupling reactions were thoroughly evaluated by the conversion of 21 alcohols and 15 ylides. Notably, compared to existing methods, which are based on precious metal complexes as catalysts, the present catalytic system is based on earth abundant manganese catalysts. The reaction can also be performed in a sequential one-pot reaction generating the phosphorus ylide in situ followed manganese catalyzed C?C and C=C bond formation. Mechanistic studies suggest that the C?C bond was generated via a borrowing hydrogen pathway and the C=C bond formation followed an acceptorless dehydrogenative coupling pathway. (Figure presented.).
Palladium-Based Catalysts Supported by Unsymmetrical XYC–1 Type Pincer Ligands: C5 Arylation of Imidazoles and Synthesis of Octinoxate Utilizing the Mizoroki–Heck Reaction
Maji, Ankur,Singh, Ovender,Singh, Sain,Mohanty, Aurobinda,Maji, Pradip K.,Ghosh, Kaushik
, p. 1596 - 1611 (2020/04/29)
A series of new unsymmetrical (XYC–1 type) palladacycles (C1–C4) were designed and synthesized with simple anchoring ligands L1–4H (L1H = 2-((2-(4-methoxybenzylidene)-1-phenylhydrazinyl)methyl)pyridine, L2H = N,N-dimethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl)aniline, L3H = N,N-diethyl-4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono)methyl) aniline and L4H = 4-(4-((2-phenyl-2-(pyridin-2-ylmethyl)hydrazono) methyl)phenyl)morpholine H = dissociable proton). Molecular structure of catalysts (C1–C4) were further established by single X-ray crystallographic studies. The catalytic performance of palladacycles (C1–C4) was explored with the direct Csp2–H arylation of imidazoles with aryl halide derivatives. These palladacycles were also applied for investigating of Mizoroki–Heck reactions with aryl halides and acrylate derivatives. During catalytic cycle in situ generated Pd(0) nanoparticles were characterized by XPS, SEM and TEM analysis and possible reaction pathways were proposed. The catalyst was employed as a pre-catalyst for the gram-scale synthesis of octinoxate, which is utilized as a UV-B sunscreen agent.
