- Nickel-Catalyzed Transformation of Aryl 2-Pyridyl Ethers via Cleavage of the Carbon-Oxygen Bond: Synthesis of Mono-α-arylated Ketones
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The nickel/IPr-catalyzed reaction of aryl 2-pyridyl ethers with propiophenone and acetophenone derivatives via C-OPy bond cleavage is performed in the presence of t -BuOLi to give mono-α-arylated ketones in moderate yields. The method is suitable for electron-rich and electron-poor ethers as well as heteroaryl ethers and tolerates a range of active functional groups.
- Li, Jing,Wang, Zhong-Xia
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- α-Arylation of (hetero)aryl ketones in aqueous surfactant media
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α-Arylation reactions can be performed in water, enabled by a designer surfactant,under mild conditions and in the absence of organic co-solvents. A multitude of aryl and heteroaryl ketones are amenable to coupling with functionalized aryl halides. Use of a lipophilic base that can gain entry to the micellar inner cores mediates enolization. In some cases, palladium loadings as low as 2500 ppm (0.25 mol%) are sufficient for coupling in a completely recyclable medium, exemplifying chemistry in water.
- Gallou, Fabrice,Lipshutz, Bruce H.,Roa, Daniel E.,Wood, Alex B.
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supporting information
p. 4858 - 4865
(2021/07/12)
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- Nickel catalyzed α-arylation of ketones with aryltrimethylammonium triflates
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Nickel-catalyzed α-arylation of ketones involving aromatic C-N cleavage has been accomplished. Intermolecular coupling of aromatic ketones with a variety of aryltrimethylammonium triflates was achieved in the presence of Ni(COD)2, IPr·HCl, and LiOBut, giving α-arylated ketones in reasonable to excellent yields.
- Li, Jing,Wang, Zhong-Xia
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p. 7579 - 7584
(2016/08/16)
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- Nickel-NHC-catalyzed α-arylation of acyclic ketones and amination of haloarenes and unexpected preferential N-arylation of 4-aminopropiophenone
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(Chemical Equation Presented) Arylation of both acyclic ketones and primary and secondary amines was achieved using a new, simple, stable, and easy-to-access nickel(II)-halide complex bearing mixed PPh3/N- heterocyclic carbene ligands as a catalyst precursor. Acyclic ketones were first arylated at the α-position with the nickel catalyst. On the other hand, less basic amines, such as diphenylamine and 4-aminobenzophenone, were more favorable in the catalytic amination of haloarenes than basic amines, contrary to previous reports. N-Arylation of 4-aminopropiophenone was found to proceed selectively without causing α-arylation of the ketone group.
- Matsubara, Kouki,Ueno, Keita,Koga, Yuji,Hara, Kenji
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p. 5069 - 5076
(2008/02/05)
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- (IPr)Pd(acac)Cl: An easily synthesized, efficient, and versatile precatalyst for C-N and C-C bond formation
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A very straightforward synthesis of (IPr)Pd(acac)Cl from two commercially available starting materials, Pd(acac)2 and IPr·HCl [acac = acetylacetonate; IPr = N,N′-bis(2,6-diisopropylphenyl)imidazol-2-ylidene], has been developed. The resulting complex, (IPr)Pd(acac)Cl (1), has proven to be a highly active PdII precatalyst in the Buchwald-Hartwig and the α-ketone arylation reactions. A wide range of substrates has been screened, including unactivated, sterically hindered, and heterocyclic aryl chlorides.
- Marion, Nicolas,Ecarnot, Elise C.,Navarro, Oscar,Amoroso, Dino,Bell, Andrew,Nolan, Steven P.
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p. 3816 - 3821
(2007/10/03)
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- NUCLEOPHILIC HETEROCYCLIC CARBENE DERIVATIVES OF PD(ACAC)2 FOR CROSS-COUPLING REACTIONS
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Embodiments in accordance with the present invention provide for a palladium complex characterized by the general Formula (I): where A is a bidentate monoanionic ligand, NHC is a nucleophilic heterocyclic carbene, and Z is an anionic ligand. Such palladium complexes are useful in initiating cross-coupling reactions.
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Page/Page column 21, 41-42, 47
(2010/11/25)
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- Suzuki-Miyaura, α-ketone arylation and dehalogenation reactions catalyzed by a versatile N-heterocyclic carbene-palladacycle complex
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The activity of the complex (IPr)PdCl(η2-N,C-C 12H7NMe2), 1 [IPr = (N,N′-bis(2,6- diisopropylphenyl)-imidazol)-2-ylidene], in the Suzuki-Miyaura cross-coupling reaction involving unactivated aryl chlorides and triflates with arylboronic acids at room temperature in technical grade 2-propanol is described. These conditions allow for the synthesis of di- and tri-ortho-substituted biaryls in very short reaction times. This complex also displays very high activity for α-ketone arylation and dehalogenation reactions of activated and unactivated aryl chlorides.
- Navarro, Oscar,Marion, Nicolas,Oonishi, Yoshihiro,Kelly III, Roy A.,Nolan, Steven P.
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p. 685 - 692
(2007/10/03)
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- Engineering reactions in crystalline solids: Prediction of intramolecular carbene rearrangements
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The unimolecular reactivity and stereoselectivity of four arylalkyl carbenes generated by a steady state irradiation of crystalline 1,2-diaryldiazopropanes were correctly predicted by taking advantage of known reaction trajectories applied to structures obtained by simple molecular mechanics calculations. It is suggested that the conformation of the diazo compound in the crystal determines the conformation of the carbene intermediate which is predisposed for a conformationally stereospecific 1,2-H shift. The results of irradiations of 1,2-diaryldiazoalkanes in crystalline media were compared with those obtained in solution and in amorphous solids. It was demonstrated that rigidity alone is not sufficient for carbene reactions to proceed with high stereoselectivity. (C) 2000 Published by Elsevier Science Ltd.
- Garcia-Garibay, Miguel A,Shin, Steve,Sanrame, Carlos N
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p. 6729 - 6737
(2007/10/03)
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