A versatile catalyst system for Suzuki–Miyaura syntheses of sterically hindered biaryls employing a cyclobutene-1,2-bis(imidazolium) salt
作者:Andreas Schmidt、Alireza Rahimi
DOI:10.1039/c001362e
日期:——
The catalyst system consisting of 3,3â²-(3,4-bis(dichloro-methylene)cyclobut-1-ene-1,2-diyl)bis(1-methyl-1H-imidazolium) bis(tetrafluoroborate), Pd(OAc)2 and NaOtBu in toluene proved to be very effective for a broad variety of SuzukiâMiyaura reactions at room temperature. It is also suited for the synthesis of sterically hindered compounds including 2,6-di-tert-butyl-2â²-substituted biaryls at elevated temperatures.
A Cyclobutene-1,2-bis(imidazolium) Salt as Preligand for Palladium-Catalyzed Cross-Coupling Reactions: Properties and Applications
作者:Alireza Rahimi、Imre Pápai、Ádám Madarász、Mimoza Gjikaj、Jan C. Namyslo、Andreas Schmidt
DOI:10.1002/ejoc.201101378
日期:2012.2
calculations on the title bis-imidazolium salt, its mono- and bis-carbenes, and its interactions with palladium are presented. In addition, we report on the scope and limitations of metal-catalyzed cross-couplingreactions performed with the title bis-imidazolium salt. The salt proved to be an efficient ligand precursor in room-temperature Suzuki–Miyaura reactions, C–C couplings with sterically extremely