1308652-64-3Relevant articles and documents
Facile Assembly of Carbazolyl-Derived Phosphine Ligands and Their Applications in Palladium-Catalyzed Sterically Hindered Arylation Processes
Leung, Man Pan,Choy, Pui Ying,Lai, Wing In,Gan, Kin Boon,Kwong, Fuk Yee
, p. 1602 - 1609 (2019/08/20)
Phosphine ligands embodying a carbazolyl motif have been found to be successful in many palladium-catalyzed biaryl syntheses and direct C-H bond arylation processes. Here, a practical scaled-up synthesis of a series of carbazolyl-derived phosphine ligands, the PhenCarPhos series, is described. The original protocol for accessing the target ligand skeleton via aromatic C-N bond formation is limited by the use of a substoichiometric amount of copper salt and diamine catalysts, which both add cost and generate purification problems (significant amounts of side products and copper residues). In order to develop a more attractive and scalable synthetic pathway, a simple nucleophilic substitution method was attempted involving simple heating of 1-bromo-2-fluorobenzene, a carbazole derivative, and KOH in DMF without inert atmosphere protection. This route enables the large-scale synthesis of the desired ligand skeletons and minimizes the association of inseparable reduction side products. Particular examples of the use of these ligands in Pd-catalyzed sterically hindered arylation processes are also shown.
Highly efficient carbazolyl-derived phosphine ligands: Application to sterically hindered biaryl couplings
Chun To, Sheung,Yee Kwong, Fuk
, p. 5079 - 5081 (2011/06/10)
A new family of phosphine ligands bearing a bulky carbazolyl scaffold is described. With the combination of ligand 2a and Pd(OAc)2, difficult tri-ortho-substituted biaryl couplings are accomplished smoothly. In particular, the catalyst loading as low as 0.02 mol% of Pd for non-activated 2,6-disubstituted aryl chloride coupling can be achieved.
