Predictable and Site-Selective Functionalization of Poly(hetero)arene Compounds by Palladium Catalysis
作者:David Lapointe、Thomas Markiewicz、Christopher J. Whipp、Amy Toderian、Keith Fagnou
DOI:10.1021/jo102081a
日期:2011.2.4
addressed by two different approaches. Site-selectivity can be obtained by applying various reaction conditions that are (hetero)arene specific to substrates that contain indoles, pyridine N-oxide, and polyfluorinated benzenes. An experimental classification of electron-rich heteroarenes based on their reactivity toward palladium-catalyzed C−H functionalization was established, the result of which correlated
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.
Highly electron-poor Buchwald-type ligand: application for Pd-catalysed direct arylation of thiophene derivatives and theoretical consideration of the secondary Pd<sup>0</sup>–arene interaction
作者:Toshinobu Korenaga、Ryo Sasaki、Kazuaki Shimada
DOI:10.1039/c5dt01991e
日期:——
Highly electron-poor SPhos ligands stabilised the Pd complex by secondary Pd0–arene interaction.
高度电子贫化的SPhos配体通过次要的Pd0-芳烃相互作用稳定了Pd配合物。
Analysis of the Palladium-Catalyzed (Aromatic)C–H Bond Metalation–Deprotonation Mechanism Spanning the Entire Spectrum of Arenes
作者:Serge I. Gorelsky、David Lapointe、Keith Fagnou
DOI:10.1021/jo202342q
日期:2012.1.6
intermediates and the analysis of bonding interactions in TS structures. The effects of remote C2 substituents on the reactivity of thiophenes were evaluated computationally and were corroborated experimentally with competition studies. We show that nucleophilicity of thiophenes, evaluated by Hammett σp parameters, correlates with each of the distortion–interaction parameters. In the final part of this manuscript
electron-deficient ligands. However, no studies have explored the relationship between the structure of the arsine ligands and their catalytic activity for direct arylation. In this study, we synthesized 27 arsine ligands with varying electron-donating and steric properties. Tris(o-trifluorotolyl)arsine, an electron-deficient and bulky ligand, exhibited the highest efficiency in a model reaction between