76708-79-7Relevant academic research and scientific papers
Palladium-catalyzed denitrogenative cross-coupling of aryl halides with arylhydrazines under mild reaction conditions
Kempasiddaiah, Manjunatha,Kandathil, Vishal,Dateer, Ramesh B.,Sasidhar,Patil, Shivaputra A.,Patil, Siddappa A.
, p. 273 - 281 (2021/01/12)
A greener approach for the synthesis of various functionalized biaryl frameworks in good to excellent yield through palladium-catalyzed denitrogenative cross-coupling of aryl halides with arylhydrazines under mild reaction conditions was developed. Catalytic system is free from the aid of expensive ligands and external oxidants. Biogenically prepared palladium nanoparticles (Pd NPs) immobilized cellulose based dip catalyst displayed excellent reactivity and selectivity toward the synthesis of a broad array of symmetrical and unsymmetrical biaryls through C–N bond cleavage in air as green oxidant. In addition, recyclability in denitrogenative cross-coupling reaction was also studied which showed excellent recycling performance and the dip catalyst remained stable even after several reuses. Thus, our newly developed strategy was successfully applied for constructing wide-ranging functional groups tolerated biaryls using arylhydrazines and aryl halides as coupling partners which is most useful for practical applications in synthetic chemistry.
Synthetic and Mechanistic Interrogation of Pd/Isocyanide-Catalyzed Cross-Coupling: π-Acidic Ligands Enable Self-Aggregating Monoligated Pd(0) Intermediates
Barnett, Brandon R.,Labios, Liezel A.,Stauber, Julia M.,Moore, Curtis E.,Rheingold, Arnold L.,Figueroa, Joshua S.
supporting information, p. 944 - 954 (2017/04/21)
Despite the large number of judiciously designed ligands that have been exploited in palladium-catalyzed cross-coupling protocols, the incorporation of ligands bearing appreciable π-acidic properties has remained significantly underexplored. Herein, we demonstrate that well-defined and low-coordinate Pd0 complexes supported by m-terphenyl isocyanides function as competent catalysts for the Suzuki-Miyaura cross-coupling of aryl bromides and arylboronic acids. Two-coordinate Pd(CNArDipp2)2 was active for the coupling of unhindered aryl bromides at room temperature in 2-propanol, while increasing the temperature to 60 °C allowed for the use of mono- or di-ortho-substituted aryl bromides. Oxidative addition of the aryl bromide was shown to proceed via a dissociative mechanism, implicating monoligated Pd(CNArDipp2) as the catalytically active intermediate. Attempts to access this fleeting species via activation of the PdII monoisocyanide PdCl(η3-C3H5)(CNArDipp2) with alkoxide base yielded the dinuclear PdI species (μ-C3H5)(μ-OiPr)[Pd(CNArDipp2)]2. Although dinuclear PdI complexes are often produced as off-cycle species when using complexes of the type PdCl(η3-allyl)L as precatalysts, this represents the first time that the comproportionation product (μ-allyl)(μ-Cl)[PdL]2 has been observed to undergo nucleophilic substitution with alkoxide, despite the fact that activating conditions for these precatalysts typically employ alkoxide bases. Remarkably, this alkoxide complex can undergo β-hydride elimination with expulsion of acetone and propene to produce two equivalents of catalytically active Pd(CNArDipp2), which can self-aggregate to yield the isolable tripalladium cluster Pd3(η2-Dipp-μ-CNArDipp2)3. This cluster is catalytically competent for the Suzuki-Miyaura reaction and functions as a formal source of monoligated Pd(CNArDipp2) in solution.
Cross-coupling of ArX with ArMgBr catalyzed by N-heterocyclic carbene-based nickel complexes
Guo, Wang-Jun,Wang, Zhong-Xia
, p. 1054 - 1061 (2013/04/10)
N-Heterocyclic carbene-based pincer nickel complexes were synthesized and characterized. These complexes efficiently catalyze cross-coupling of aryl Grignard reagents with aryl chlorides or fluorides under mild conditions.
Ag(I)-catalyzed carbon-carbon bond formation between a ketone and an allylic C-H bond
Pati, Kamalkishore,Liu, Rai-Shung
supporting information; experimental part, p. 6049 - 6051 (2012/07/13)
We report a silver-catalyzed cyclization of 1-(2,2-dimethyl-cyclopropyl) methyl ketones to give 1,2,4-trisubstituted benzenes. These reactions comprise an initial cyclopropane cleavage, followed by an aromatization of the resulting 4-en-1-one intermediate
Synthesis of biaryls via AlCl3 catalyzed domino reaction involving cyclization, dehydration, and oxidation
Narender, Tadigoppula,Sarkar, Satinath,Rajendar, Kandikonda,Tiwari, Sriniwas
, p. 6140 - 6143 (2012/01/03)
A new chemical access has been developed to synthesize biaryls from substituted acetophenones, phenylacetones, dihydrochalcone, and 2-acetylnaphthalene in reasonably good yields at room temperature via a domino reaction sequence of AlCl3 catalyzed cyclization, dehydration, and then oxidation.
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.
The effect of ortho-substitution on the efficacy of biphenyls in mediating electron transfer from lithium
Donohoe, Timothy J.,Kershaw, Neil M.,Baron, Ronan,Compton, Richard G.
experimental part, p. 5377 - 5384 (2009/11/30)
A systematic study into the effect of increasing ortho-substitution of a range of biphenyls with respect to their ability to mediate electron transfer from lithium metal is described. A synthetic investigation has demonstrated the requirements for effecti
PREPARATION OF SOME TRIMETHYL- AND METHYLETHYLBIPHENYLS AND REACTIVITY OF AROMATIC HYDROCARBONS IN THE GOMBERG REACTION
Novrocik, Jan,Novrocikova, Marta,Titz, Milos
, p. 3140 - 3149 (2007/10/02)
Trimethyl- and methylethylbiphenyls with the alkyl groups in the both phenyl rings have been prepared by the Gomberg reaction and identified by the capillary gas-liquid chromatography.Depending on choice of the aromatic hydrocarbon either individual isomers or their mixtures (three at the most) have been obtained which were contaminated with compounds of diarylmethane type in many cases.The methylethylbiphenyls have only been prepared as mixtures contaminated with diarylmethanes.These side products have been prepared by independent syntheses.A method has been developed for isolation and separation of mixtures of trimethyl- and methylethylbiphenyls from the reaction products containing tarry products.The method is suitable for preparation of small amounts of some analytical standards.The HMO method has been used for calculation of values of the radical superdelocalizabilities at individual centres in the molecules of o-, m- and p-xylene, toluene and ethylbenzene, and these values have been compared with composition of the Gomberg reaction products from these hydrocarbons.The competitive technique has been used for comparison of the reactivities of the mentioned aromatic substrates in the Gomberg reactions.
