<i>Ortho</i>-Selective Cross-Coupling of Fluorobenzenes with Grignard Reagents: Acceleration by Electron-Donating<i>Ortho</i>-Directing Groups
作者:Kei Manabe、Shunpei Ishikawa
DOI:10.1055/s-2008-1067182
日期:2008.8
Fluorobenzenes with directing groups such as hydroxy, hydroxymethyl, and ammo underwent ortho-selective cross-coupling with Grignardreagents in the presence of palladium-based catalysts, with dichlorobis(tricyclohexylphosphine)palladium [PdCl 2 (PCy 3 ) 2 ] found to be the optimum catalyst. Fluoro and chloro groups at positions other than ortho to the directing groups survived under the reaction conditions
Highly Ortho-Selective Cross-Coupling of Dichlorobenzene Derivatives with Grignard Reagents
作者:Shunpei Ishikawa、Kei Manabe
DOI:10.1021/ol702646s
日期:2007.12.1
Highly ortho-selective cross-coupling of dichlorobenzene derivatives with Grignard reagents was realized using a combination of Pd-2(dba)(3) and PCy3. Use of hydroxylated terphenylphosphines further improved the reactions of dichlorophenol and dichloroaniline.
Synthesis of Substituted Monohalobenzenes via Ortho-Selective Cross-Coupling of Dihalobenzenes with Electron-Donating Ortho-Directing Groups
作者:Kei Manabe、Shunpei Ishikawa
DOI:10.1055/s-2008-1067270
日期:2008.10
Dihalobenzenes that possess directing groups such as OH, CH 2 OH, NH 2 , NHAc, or NHBoc were subjected to ortho-selective cross-coupling with Grignard reagents in the presence of palladium-based catalysts to give the corresponding substituted monohalobenzenes. For the dibromo- and dichlorophenols and anilines, hydroxylated terphenylphosphines 1 and 2 were found to be effective ligands for palladium