80331-39-1Relevant academic research and scientific papers
Palladium-catalyzed redox cascade for direct β-arylation of ketones
Huang, Zhongxing,Dong, Guangbin
supporting information, p. 3253 - 3265 (2018/05/04)
Herein we report a full article about the detailed design and development of two palladium-catalyzed redox cascade methods that enable direct β-arylation of ketones. Palladium-catalyzed ketone dehydrogenation, aryl-X bond activation and conjugate addition were merged into a redox-neutral catalytic cycle. Non-metal-based aryl electrophiles were used as both the oxidant and the aryl source. The β-arylation with aryl iodides was achieved site-selectively with Pd(TFA)2/P(i-Pr)3 as the precatalyst and AgTFA as the iodide scavenger. Both cyclic and linear ketones can react to give β-aryl ketones with excellent functional group tolerance. The β-arylation with diaryliodonium salts was realized without stoichiometric heavy metal additives, and proved to be redox-neutral. A wider substrate scope regarding aryl groups and ketones was obtained for the arylation with diaryliodonium salts, and the possible involvement of palladium nanoparticles as the active catalyst was examined and discussed.
DIRECT B-ARYLATION OF CARBONYL COMPOUNDS
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Paragraph 0123-0125; 128, (2016/09/12)
Disclosed is a method for the β-C—H H functionalization of carbonyl compounds that is both selective and broadly applicable. The methods provide direct β-arylation of carbonyl compound with a diverse array of aryl or heteroaryl halides, aryl or heteroryl tosylate, aryl or heteroaryl triflates, or diaryliodonium salts, by palladium catalysis in the presence of a ligand and promoter.
Palladium-catalyzed direct β-arylation of ketones with diaryliodonium salts: A stoichiometric heavy metal-free and user-friendly approach
Huang, Zhongxing,Sam, Quynh P.,Dong, Guangbin
, p. 5491 - 5498 (2015/09/28)
We herein report a new protocol for the Pd-catalyzed β-arylation of ketones without stoichiometric heavy metals. Widely accessible diaryliodonium salts are used as both the oxidant and aryl source. This tandem redox catalysis merges ketone dehydrogenation and conjugate addition without an additional oxidant or reductant. This transformation features the use of a unique bis-N-tosylsulfilimine ligand and the combination of potassium trifluoroacetate/trifluoroacetic acid to maintain an appropriate acidity of the reaction medium. The reaction tolerates both air and moisture, and shows a broad substrate scope. Kinetics studies, along with filtration and poisoning tests, support the involvement of palladium nanoparticles in the catalysis.
THE PALLADIUM-CATALYSED CONJUGATE ADDITION TYPE REACTION OF ARYLMERCURY COMPOUNDS WITH α,β-UNSATURATED KETONES IN A TWO-PHASE SYSTEM
Cacchi, S.,Misiti, D.
, p. 2941 - 2946 (2007/10/02)
Pd-catalysed reaction of arylmercury compounds with α,β-enones in an acidic two-phase system provides a mild and selective way to β-aryl ketones.The present conjugate addition type reaction may accomodate a wide variety of functional groups.Thus, aryl units containing electron-donating and electron-withdrawing substituents such as -Me, -Cl, -CHO, -COMe, -COOMe, -COOH, -OH, -OMe, -NHCOMe and NO2 were succesfully transfered to the β C atom of benzalacetone.A number of α,β-enones were also treated with 3-formylphenyl mercury chloride to give the corresponding β-(3-formylphenyl) derivatives.The main limitation seems to arise from steric hindrance in the starting α,β-enonic system.Substituents in the aryl moiety of the organomercury compounds were found to affect the transmetalation steps in the direction expected for a rate determining ?-complex formation.
