15424-39-2Relevant academic research and scientific papers
Palladium-catalyzed amination of aryl sulfides with anilines
Sugahara, Tomohiro,Murakami, Kei,Yorimitsu, Hideki,Osuka, Atsuhiro
, p. 9329 - 9333,5 (2014)
A combination of a palladium-NHC catalyst and potassium hexamethyldisilazide enables the amination of aryl sulfides with anilines to afford a wide variety of diarylamines. The reaction conditions are versatile enough for the reaction of even bulky ortho-substituted aryl sulfides. This amination can be applied to the modular synthesis of N-aryl carbazoles from the corresponding ortho-bromothioanisoles. As aryl sulfoxides undergo extended Pummerer reactions to afford ortho-substituted aryl sulfides, the Pummerer products are thus useful substrates for the amination to culminate in efficient syntheses of a 2-anilinobenzothiophene and an indole as proof-of-principle of the utility of the extended Pummerer reaction/amination cascade. Switching S to N: Transformation of inert C-S bonds of aryl sulfides into C-N bonds is achieved using a palladium complex with an N-heterocyclic carbene ligand. Thanks to the efficient conditions for amination of bulky sulfides, the synthesis of carbazole products from 2-biphenylylamine is achieved through oxidative C-N bond formation. When combined with extended Pummerer reactions, intriguing nitrogen-containing molecules are prepared.
N-Heterocyclic Olefin-Ligated Palladium(II) Complexes as Pre-Catalysts for Buchwald–Hartwig Aminations
Watson, Ian C.,Schumann, André,Yu, Haoyang,Davy, Emma C.,McDonald, Robert,Ferguson, Michael J.,Hering-Junghans, Christian,Rivard, Eric
supporting information, p. 9678 - 9690 (2019/07/09)
New N-heterocyclic olefins (NHOs) are described with functionalization on the ligand heterocyclic backbone and terminal alkylidene positions. Various PdII–NHO complexes have been formed and their use as pre-catalysts in Buchwald–Hartwig aminations was explored. The most active system for catalytic C?N bond formation between hindered arylamine and arylhalide substrates was accessed by combining a backbone methylated NHO with [Pd(cinnamyl)Cl]2 in the presence of NaOtBu as a base. In these active systems evidence suggests that catalysis is mediated by colloidal palladium metal, highlighting a different coordination ability of NHOs in comparison with commonly used N-heterocyclic carbene co-ligands.
