25506-47-2Relevant academic research and scientific papers
Synthesis of biaryls by Pd-catalyzed decarboxylative homo- and heterocoupling of substituted benzoic acids
Xie, Kai,Wang, Sizhuo,Yang, Zhiyong,Liu, Jidan,Wang, Anwei,Li, Xiujian,Tan, Ze,Guo, Can-Cheng,Deng, Wei
supporting information; experimental part, p. 5787 - 5790 (2011/11/06)
By carefully choosing the right substrate ratio, catalyst combination, and base, symmetrical and unsymmetrical biaryls can be readily synthesized through the Pd-catalyzed decarboxylative homo- and heterocoupling of substituted benzoic acids. The reaction gave the desired products in 40-90% yield and is compatible with 2-nitro-, 2-methoxy-, 2-fluoro-, and 2-chloro-substituted benzoic acids. With the correct substrate ratio, catalyst combination, and base, symmetrical and unsymmetrical biaryls can be readily synthesized through the Pd-catalyzed decarboxylative homo- and heterocoupling of substituted benzoic acids.
Fluorinated biphenyls from aromatic arylations with pentafluorobenzenediazonium and related cations. Competition between arylation and azo coupling
Kosynkin, Dmitry,Bockman, T. Michael,Kochi, Jay K.
, p. 2003 - 2012 (2007/10/03)
High yields of the mixed perfluorinated biaryls (C6F5-Ar) are obtained by the catalytic dediazonlatlon of the pentafluorobenzenediazonium salt (C6F5N2+BF4-) in acetonitrile solutions containing various aromatic substrates (ArH) together with small amounts of iodide salts. Activated (electron-rich) as well as deactivated (electron-poor) arenes are successfully pentafluorophenylated by this method. The arylation is distinct from the azo coupling of the same substrates, which takes place in the absence of the iodide catalyst and yields the corresponding diazene (C6F5N=N-Ar) as product. The catalytic role of iodide, and the isomeric product distributions obtained with this procedure indicate that the arylation proceeds via the pentafluorophenyl radical in a efficient homolytic chain process. Since azo coupling involves electrophilic aromatic substitution of electron-rich ArH by C6F5N2+, the two competing pathways are distinct and do not have reactive intermediates in common.
