1146127-11-8Relevant articles and documents
Mechanistic investigations of Cu-catalyzed fluorination of diaryliodonium salts: Elaborating the CuI/CuIII manifold in copper catalysis
Ichiishi, Naoko,Canty, Allan J.,Yates, Brian F.,Sanford, Melanie S.
, p. 5525 - 5534 (2014)
A combination of experimental and density functional theory (DFT) investigations suggests that the Cu-catalyzed fluorination of unsymmetrical diaryliodonium salts with general structure [Mes(Ar)I]+ in N,N′-dimethylformamide proceeds through a CuI/CuIII catalytic cycle. A low concentration of fluoride relative to combined iodonium reagent plus copper ensures that [Mes(Ar)I]+ is available as the reactive species for oxidative "Ar+" transfer to a CuI center containing one or two fluoride ligands. A series of different possible CuI active catalysts (containing fluoride, triflate, and DMF ligands) have been evaluated computationally, and all show low-energy pathways to fluorinated products. The oxidation of these CuI species by [Mes(Ar)I]+ to form cis-Ar(F)CuIII intermediates is proposed to be rate-limiting in all cases. Ar-F bond-forming reductive elimination from CuIII is computed to be very facile in all of the systems examined. The conclusions of the DFT experiments are supported by several experimental studies, including tests showing that CuI is formed rapidly under the reaction conditions and that the fluoride concentration strongly impacts the reaction yields/selectivities.
Copper-Catalyzed Selective N-Arylation of Oxadiazolones by Diaryliodonium Salts
Soldatova, Natalia S.,Semenov, Artem V.,Geyl, Kirill K.,Baykov, Sergey V.,Shetnev, Anton A.,Konstantinova, Anna S.,Korsakov, Mikhail M.,Yusubov, Mekhman S.,Postnikov, Pavel S.
supporting information, p. 3566 - 3576 (2021/06/16)
Here, we report the method for copper-catalyzed N-arylation of diverse oxadiazolones by diaryliodonium salts under mild conditions in high yields (up to 92%) using available CuI as a catalyst. The developed method allows utilizing both symmetric and unsymmetric diaryliodonium salts bearing auxiliary groups such as 2,4,6-trimethoxyphenyl (TMP). We found that the steric effects in aryl moieties determined the chemoselectivity of N- and O-arylation of the 1,2,4-oxadiazol-5(4H)-ones. Mesityl-substituted diaryliodonium salts demonstrated the high potential as a selective arylation reagent. The structural study suggests that steric accessibility of N-atom in 1,2,4-oxadiazol-5(4H)-ones impact to arylation with sterically hindered diaryliodonium salts. The synthetic application of proposed method was also demonstrated on selective arylation of 1,3,4-oxadiazol-2(3H)-ones and 1,2,4-oxadiazole-5-thiol. (Figure presented.).
Versatile and base-free copper-catalyzed α-arylations of aromatic ketones using diaryliodonium salts
Bouquin, Maxime,Jaroschik, Florian,Taillefer, Marc
supporting information, (2021/06/11)
A ligand and base-free copper catalyzed synthetic method for the efficient α-arylation of aromatic ketones is described. In order to avoid strong bases, ketone-derived silyl enol ethers were employed. Their reaction with diaryliodonium salts as aryl source provided the intermolecular C–C coupling displaying good functional group tolerance and requiring low catalyst loading.
