Ferrocenyl palladacycles derived from unsymmetrical pincer-type ligands: evidence of Pd(0) nanoparticle generation during the Suzuki–Miyaura reaction and applications in the direct arylation of thiazoles and isoxazoles
作者:Ankur Maji、Anshu Singh、Aurobinda Mohanty、Pradip K. Maji、Kaushik Ghosh
DOI:10.1039/c9dt03465j
日期:——
Mechanistic investigation authenticated the generation of Pd(0) nanoparticles during the catalytic cycle and the nanoparticles were characterized by XPS, SEM and TEM analysis. Direct C–H arylation of thiazole and isoxazole derivatives employing these ferrocenyl-palladacycle complexes was examined. The reaction model for the arylation reaction implicating the in situ generation of Pd(0) nanoparticles was
Conditions for the palladium-catalyzed directarylation of a wide range of heterocycles with aryl bromides are reported. Those conditions employ a stoichiometric ratio of both coupling partners, as well as a substoichiometric quantity of pivalicacid, which results in significantly faster reactions. An evaluation of the influence of the nature of the aryl halide has also been carried out.
A convenient phosphine-free palladium-catalyzed direct arylation of thiazole under mild aerobic conditions
作者:Xiao-Xi He、Yan-Fang Li、Ju Huang、Dong-Sheng Shen、Feng-Shou Liu
DOI:10.1016/j.jorganchem.2015.12.009
日期:2016.2
A series of bulky amine palladium complexes [(Ar-NH2)2PdCl2]} were synthesized and characterized. The catalytic activity of the palladium complexes was evaluated via the direct C–H arylation of thiazoles with aryl bromides in aerobic conditions at 80–100 °C. Under the optimal conditions, 0.5–0.05 mol% of the bulky palladium complexes were found to be very efficient and produced the desired cross-coupling
A Robust and Efficient Catalyst Possessing an Electron-Deficient Ligand for the Palladium-Catalyzed Direct Arylation of Heteroarenes
作者:Alexandra Jakab、Zoltán Dalicsek、Tibor Soós
DOI:10.1002/ejoc.201402586
日期:2015.1
The exploration of the directarylation capacity of a unique, thermally stable, and air-stable Pd0–phosphine catalyst is reported. Besides decisively contributing to catalyst robustness, the electron-deficient trifluoromethyl-substituted triphenylphosphine ligands make the palladium center more electron-deficient and accelerate the directarylation step. The combination of only 0.5–2 mol-% of the catalyst
Expanded scope of heterocyclic biaryl synthesis via a palladium-catalysed thermal decarboxylative cross-coupling reaction
作者:Marie Kissane、Orla A. McNamara、David Mitchell、David M. Coppert、Humphrey A. Moynihan、Kurt T. Lorenz、Anita R. Maguire
DOI:10.1016/j.tetlet.2011.11.051
日期:2012.1
The palladium-catalysed decarboxylativecross-coupling of heterocyclic aromaticcarboxylates and aryl halides is described. The cross-coupling proceeds under relatively mild conditions using catalytic Pd(0) and tetrabutylammonium bromide (TBAB). Utilizing a mixed solvent system consisting of N,N-dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP), the cross-coupling system operated at temperatures