611-61-0Relevant academic research and scientific papers
Preparation of metal-immobilized methacrylate-based monolithic columns for flow-through cross-coupling reactions
Sabarudin, Akhmad,Shu, Shin,Umemura, Tomonari,Yamamoto, Kazuhiro
, (2021/12/17)
With the aim of developing efficient flow-through microreactors for high-throughput organic synthesis, in this work, microreactors were fabricated by chemically immobilizing palladium-, nickel-, iron-, and copper-based catalysts onto ligand-modified poly(glycidyl methacrylate-co-ethylene dimethacrylate) [poly(GMA-co-EDMA)] monoliths, which were prepared inside a silicosteel tubing (10 cm long with an inner diameter of 1.0 mm) and modified with several ligands including 5-amino-1,10-phenanthroline (APHEN), iminodiacetic acid (IDA), and iminodimethyl phosphonic acid (IDP). The performance of the resulting microreactors in Suzuki?Miyaura cross-coupling reactions was evaluated, finding that the poly(GMA-co-EDMA) monolith chemically modified with 5-amino-1,10-phenanthroline as a binding site for the palladium catalyst provided an excellent flow-through performance, enabling highly efficient and rapid reactions with high product yields. Moreover, this monolithic microreactor maintained its good activity and efficiency during prolonged use.
PREPARATION OF DIPHENYL COMPOUNDS
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Paragraph 0040, (2019/10/29)
This disclosure relates to the preparation of diphenyl compounds, especially dimethylbiphenyl compounds, in which there is one methyl group on each ring, and their oxidized analogues. These compounds, and particularly alkylated biphenyl compounds and biphenylcarboxylic acids, alcohols and esters, are useful intermediates in the production of a variety of commercially valuable products, including polyesters and plasticizers for PVC and other polymer compositions.
OXIDATION OF METHYL-SUBSTITUTED BIPHENYL COMPOUNDS
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Paragraph 0064-0066, (2017/11/04)
A process for oxidizing methyl-substituted biphenyl compounds comprises contacting a mixture comprising isomers of at least one methyl-substituted biphenyl compound with a source of oxygen, wherein the mixture comprises at least 20 wt% of isomer(s) having a methyl group at a 2-position or a 3-position on at least one benzene ring and at least 50 wt% of isomer(s) having a methyl group at a 4-position on at least one benzene ring, wherein said percentages are based on the total weight of the at least one methylbiphenyl compound in the mixture.
A fluorous ethylenediamine promoted direct C-H arylation of unactivated arenes with aryl halides
Zhu, Yi-Wei,Shi, Yi-Xin
supporting information, p. 10 - 13 (2016/07/06)
A novel and recyclable fluorous ethylenediamine was prepared. Together with potassium tert-butoxide, the fluorous ethylenediamine showed a good activity in promoting the coupling of aryl halides with benzene derivatives without the aid of transition-metal catalysts. Furthermore, a chain homolytic aromatic substitution mechanism was proposed in this paper.
Transition-Metal-Free Cross-Coupling of Aryl Halides with Arylstannanes
He, Qing,Wang, Liwen,Liang, Yong,Zhang, Zunting,Wnuk, Stanislaw F.
, p. 9422 - 9427 (2016/10/17)
Transition-metal-free LiCl-promoted cross-coupling reactions of tetraphenyltin, trichlorophenyl-, dichlorodiphenyl-, and chlorotriphenylstannanes with aryl halides in DMF provided access to biaryls in good to high yields. Up to four phenyl groups were transferred from the organostannanes substrates. The aryls bearing electron-withdrawing groups in either halides or organotin substrates gave coupling products in higher yields. The methodology has been applied for the efficient synthesis of ipriflavones.
Di-tert-butyl peroxide promoted direct C-H arylation of unactivated arenes with aryl halides
Zhu, Yi-Wei,Yi, Wen-Bin,Qian, Jin-Long,Cai, Chun
, p. 733 - 735 (2014/03/21)
Di-tert-butyl peroxide can smoothly promote the coupling of aryl halides with benzene derivatives without the aid of transition-metal catalysts through a chain homolytic aromatic substitution mechanism in the presence of potassium tert-butoxide. Radical reasoning: Di-tert-butyl peroxide and potassium tert-butoxide smoothly direct the C-H arylation of unactivated benzene derivatives with aryl halides without the aid of a transition metal. Reactions occur through a base-promoted homolytic aromatic substitution process and involve aryl radicals and aryl radical anions as intermediates. The process to synthesize biaryl compounds is high yielding and practical.
Reactivity of [K3(phen)8][Cu(NPh2) 2]3 - A possible intermediate in the copper(i)-catalyzed N-arylation of N-phenylaniline
Tseng, Chia-Kai,Lee, Chi-Rung,Tseng, Mei-Chun,Han, Chien-Chung,Shyu, Shin-Guang
, p. 7020 - 7027 (2014/05/06)
Complex [K3(phen)8][Cu(NPh2) 2]3 (1, phen = phenanthroline) was isolated from the catalytic C-N cross coupling reaction based on the CuI-phen-tBuOK catalytic system. Complex 1 can react with 4-iodotoluene to give 4-methyl-N,N- diphenylaniline (3a) in 50% yield (based on all available NPh2 - ligands of complex 1). In addition, 1 can also work as an effective catalyst for the C-N coupling reactions under the same reaction conditions, indicating that 1 may be an effective intermediate of the catalytic system. In the presence of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), a radical scavenger, the stoichiometric reaction between complex 1 and 4-iodotoluene was significantly quenched to give a low yield of 12%. The results suggest that the radical path dominates in the reaction, with (phen)KNPh2 as the possible radical source. The structures of 1 and (phen)KNPh2 were both determined by single crystal X-ray diffraction studies.
Nickel-catalyzed hydrogenolysis of unactivated carbon-cyano bonds
Patra, Tuhin,Agasti, Soumitra,Modak, Atanu,Maiti, Debabrata
supporting information, p. 8362 - 8364 (2013/09/23)
Selective hydrogenolysis of C-CN bonds can allow chemists to take advantage of ortho-directing ability, α-C-H acidity and electron withdrawing ability of the cyano group for synthetic manipulations. We have discovered hydrogenolysis of aryl and aliphatic cyanides under just 1 bar of hydrogen by using a nickel catalyst. This protocol was applied in the aryl cyanide directed functionalization reaction and α-substitution of benzyl cyanides.
C-H arylation of unactivated arenes with aryl halides catalyzed by cobalt porphyrin
To, Ching Tat,Chan, Tek Long,Li, Bao Zhu,Hui, Ying Ying,Kwok, Tsz Yiu,Lam, Suet Yu,Chan, Kin Shing
supporting information; experimental part, p. 1023 - 1026 (2011/03/20)
A general procedure for cobalt-catalyzed direct C-H arylation of unactivated arenes has been discovered. This method employs aryl halides as the direct coupling partners with arenes without using any Grignard-type reagents. This catalysis opens a new methodology for the preparation of symmetrical as well as unsymmetrical biaryls in a user-friendly approach.
Synthesis, characterization and catalytic behaviors of neutral nickel complexes: Arylnickel N-alkyl-6-(1-(arylimino)ethyl)picolinamide
Shen, Miao,Hao, Peng,Sun, Wen-Hua
, p. 1683 - 1695 (2008/09/18)
A series of novel neutral nickel complexes, aryl (phenyl or naphthyl) nickel N-alkyl-6-(1-(arylimino)ethyl)picolinamides, were synthesized and characterized by NMR and IR spectroscopy and elemental analysis. Single-crystal X-ray diffraction analyses of the complexes C2, C3 and C7 reveal distorted square-planar geometry along with the molecular structure of one free ligand L1. On activation with diethylaluminum chloride (Et2AlCl), the nickel complexes exhibited moderate catalytic activities for ethylene oligomerization, and the catalytic activity was up to 2.45 × 105 g mol-1(Ni) h-1 in the presence of 1 equiv. PPh3. Moreover, these complexes also exhibit moderate activities for Kumada-Corriu reaction and polymerization of methyl methacrylate.
