29460-97-7Relevant academic research and scientific papers
3,3'-((Arylmethylene)bis(4-methoxy-3,1-phenylene)) dipyridine derivatives as convenient ligands for Suzuki–Miyaura chemo- and homoselective cross-coupling reactions
Hosseini, Raziyeh,Mohammadiannejad, Kazem,Ranjbar-Karimi, Reza
, (2021/08/25)
Four novel N,N-bidentate triarylmethane-based ligands bearing β-pyridyl residues have been prepared and the catalytic activity of their in-situ generated palladium complexes were studied in the Suzuki–Miyaura cross-coupling reactions. Air and moisture stable 3,3'-((arylmethylene)bis(4-methoxy-3,1-phenylene))dipyridines L1-3 showed excellent activity in the Suzuki coupling reactions of aryl halides with aryl boronic acids under thermal and sonochemical reaction conditions. The described methodology provided good to high yields in short reaction times at ambient conditions. Moreover, it offered a straightforward way for Suzuki–Miyaura chemo- and homoselective cross-coupling of aryl halides with phenyl boronic acid. The structures of synthesized compounds were fully characterized by FT-IR, 1H-NMR, 13C-NMR, and elemental analyses. The coordination of palladium acetate to nitrogen sites of L1 was also studied using FTIR spectroscopy, EDX analysis and SEM observations. Graphic abstract: The in-situ generated Pd-complexes of N,N-bidentate ligands L1-3 are described as robust and highly effective catalytic systems for the Suzuki cross-coupling of aryl halides with aryl boronic acids under thermal and sonochemical reaction conditions.[Figure not available: see fulltext.]
Photoelectric properties of aromatic triangular tri-palladium complexes and their catalytic applications in the Suzuki-Miyaura coupling reaction
Li, Jia,Li, Xujun,Liu, Xiang,Maestri, Giovanni,Malacria, Max,Wang, Xiaoshuang,Wang, Yanlan,Wu, Lingang
supporting information, p. 11834 - 11842 (2021/09/06)
The photoelectric properties and catalytic activities of substituted triphenylphosphine and sulfur/selenium ligand supported aromatic triangular tri-palladium complexes1-4, abbreviated as [Pd3]+, were investigated. The cyclic voltammogram of [Pd3]+in CH3CN-nBu4NPF6showed a single quasi-reversible wave which was consistent with their robust property and provided preliminary proof for their electron transfer processes in catalysis. With excitation at 267 nm, [Pd3]+exhibited strong ratiometric fluorescence at 550 and 780 nm at a temperature gradient from 77 K to 287 K. These peculiar triangular tri-palladium complexes showed excellent catalytic activities and exclusive reactivity with aryl iodides over the other halogenated aromatics in the Suzuki-Miyaura coupling reaction. The electronic and steric hindrance effects of substituents on the aryl iodides and aryl boronic acids including heteroaromatics like pyridine, pyrazine and thiophenes were explored and most substrates achieved up to 99% of yields. (2-[1,1′-Biphenyl]-2-ylbenzothiazole) which was analogous to the selective cyclooxygenase-2 (COX-2) inhibitors was also synthesized with our tri-palladium catalyst and gave good isolated yield (94%). The study of the catalytic process revealed that the mechanism of the reaction may involve the replacement of the sulphur ligand on [Pd3]+by iodine from aryl iodides, which was beneficial for the matching of C-I bond energy.
Anthracene-containing dimer skeleton ligand and preparation method thereof, and application in metal catalytic reaction
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Paragraph 0143-0146, (2021/01/29)
The invention provides an anthracene dimer derivative phosphine-containing ligand as shown in the following formula I, wherein the anthracene dimer derivative phosphine-containing ligand can be used for a series of transition metal catalyzed coupling reac
Au(I)-Catalyzed Hydration of 1-Iodoalkynes Leading to α-Iodoketones
Cazin, Catherine S. J.,Gómez-Herrera, Alberto,Hashim, Ishfaq Ibni,Nahra, Fady,Porré, Marre
, p. 6790 - 6794 (2020/11/23)
A catalytic protocol for the Au(I)-catalyzed hydration of 1-iodoalkynes is disclosed. The use of Au(I)–NHC catalyst enabled the straightforward synthesis of a variety of α-iodomethyl ketones in good to excellent yields. The utility of this simple method is further highlighted by showcasing iodination/hydration and hydration/oxidation sequential protocols leading to the construction of molecular complexity.
NaH-mediated direct C-H arylation in the presence of 1,10-phenanthroline
Nozawa-Kumada, Kanako,Iwakawa, Yuki,Onuma, So,Shigeno, Masanori,Kondo, Yoshinori
supporting information, p. 7773 - 7776 (2020/07/27)
Transition-metal-free coupling of haloarenes with unactivated arenes has been developed in the presence of NaH and 1,10-phenanthroline. Various haloarenes bearing methyl, methoxy, halogen (fluoride, chloride, and bromide), cyano, trifluoromethyl, ester, and amide groups can be cross-coupled with unactivated arenes, or heteroarenes in this reaction.
Organocatalyst in Direct C(sp2)-H Arylation of Unactivated Arenes: [1-(2-Hydroxyethyl)-piperazine]-Catalyzed Inter-/Intra-molecular C-H Bond Activation
Yadav, Lalit,Tiwari, Mohit K.,Shyamlal, Bharti Rajesh Kumar,Chaudhary, Sandeep
, p. 8121 - 8141 (2020/07/16)
This article describes the identification of 1-(2-hydroxyethyl)-piperazine as a new, cost-effective, highly efficient organocatalyst, which promotes both inter- A nd intra-molecular direct C(sp2)-H arylations of unactivated arenes in the presence of potassium tert-butoxide. While the inter-molecular C-H arylation of unactivated benzenes with aryl halides (Ar-X; X = I, Br, Cl) toward biaryl syntheses underwent smoothly in the presence of only 10 mol percent organocatalyst, the intra-molecular C-H arylation catalytic system composed of 40 mol percent each of the catalyst and the additive (4-dimethylaminopyridine (DMAP)). The novel catalyst was also able to perform both inter- A nd intra-molecular direct arylations simultaneously in a single pot. The mechanistic studies confirmed the involvement of aryl radical anions and proceeded via a single-electron-transfer (SET) mechanism. The large substrate scope, high functional group tolerance, competition experiments, gram-scale synthesis, and kinetic studies further highlight the importance and versatile nature of the methodology as well as the compatibility of the new catalyst. To the best of our knowledge, this is the first report on any organocatalyst that reported detailed investigations of both inter- A nd intra-molecular direct C(sp2)-H arylations of unactivated arenes in a single representation.
Synthesis of Enaminone-Pd(II) Complexes and Their Application in Catalysing Aqueous Suzuki-Miyaura Cross Coupling Reaction
Fu, Leiqing,Cao, Xiaoji,Wan, Jie-Ping,Liu, Yunyun
, p. 254 - 258 (2020/01/25)
A series of Pd(II)-enaminone complexes, termed Pd(eao)2, have been synthesized and characterized. The investigation on the catalytic activities of these new Pd(II)-reagents has proved that the Pd(eao)2-1 possesses excellent catalytic activity for the Suzuki- Miyaura cross coupling reactions of aryl bromides/chlorides with aryl/vinyl boronic acids in the environmentally benign media of aqueous PEG400 at low loading (5 mol‰). The superiority of this Pd(II)-reagent to those commercial Pd(II) and Pd(0) catalysts in catalyzing the reactions has been confirmed by parallel experiments. What's more, Pd(eao)2-2 has been found as a practical catalyst for the homo-coupling reactions of aryl boronic acids.
Direct C-H photoarylation of diazines using aryldiazonium salts and visible-light
Silva, Rodrigo C.,Villela, Lucas F.,Brocksom, Timothy J.,De Oliveira, Kleber T.
, p. 31115 - 31122 (2020/09/23)
In this study, direct C-H photoarylation of pyrazine with aryldiazonium salts under visible-light irradiation (blue-LEDs) is described, and additional examples including photoarylations of pyrimidine and pyridazine are also covered. The corresponding aryl-diazines were prepared in yields up to 84% only by mixing and irradiating the reaction with no need for an additional photocatalyst. We demonstrate the efficacy of this protocol by the scope with electron-donor, -neutral, and -withdrawing groups attached at the ortho, meta, and para positions of the aryldiazonium salts; the results are better than those reported for ruthenium-complex mediated photoarylations. Additionally, we demonstrate the robustness of this methodology with a 5 mmol scaled-up experiment. Mechanistic studies were carried out giving support to the proposal of a photocatalyzed approach by an electron donor-acceptor (EDA) complex, also highlighting the crucial role that solvents play in the formation of the EDA complex. This journal is
N-Heterocarbene Palladium Complexes with Dianisole Backbones: Synthesis, Structure, and Catalysis
Li, Dong-Hui,He, Xu-Xian,Xu, Chang,Huang, Fei-Dong,Liu, Ning,Shen, Dong-Sheng,Liu, Feng-Shou
, p. 2539 - 2552 (2019/06/17)
A series of palladium N-heterocyclic carbenes (NHCs), complexes C1-C5, bearing dianisole backbones and substituted N-aryl moieties have been synthesized and characterized. The electronic effect as well as the steric environment of the NHC ligands has been assessed. The synthesized palladium complexes were applied for Suzuki-Miyaura cross-coupling reactions under aerobic conditions. The relationship between the catalytic structure and catalytic performance was then extensively investigated. Upon optimizing the reaction conditions, the C4 was found to be highly efficient to catalyze the cross-coupling of (hetero)aryl chlorides with (hetero)arylboronic acids at a 0.1 mol % palladium loading.
Generation of Aryl Radicals from Aryl Halides: Rongalite-Promoted Transition-Metal-Free Arylation
Yu, Fazhi,Mao, Runyu,Yu, Mingcheng,Gu, Xianfeng,Wang, Yonghui
, p. 9946 - 9956 (2019/09/04)
A new and practical method for the generation of aryl radicals from aryl halides is reported. Rongalite as a novel precursor of super electron donors was used to initiate a series of electron-catalyzed reactions under mild conditions. These transition-metal-free radical chain reactions enable the efficient formation of C-C, C-S, and C-P bonds through homolytic aromatic substitution or SRN1 reactions. Moreover, the synthesis of antipsychotic drug Quetiapine was performed on gram scale through the described method. This protocol demonstrated its potential as a promising arylation method in organic synthesis.
