97053-04-8Relevant articles and documents
Synergistic Ligand Effect between N-Heterocyclic Carbene (NHC) and Bicyclic Phosphoramidite (Briphos) Ligands in Pd-Catalyzed Amination
Kim, Miji,Shin, Taeil,Lee, Ansoo,Kim, Hyunwoo
supporting information, p. 3253 - 3258 (2018/10/02)
A synergistic ligand effect between NHC and phosphorus ligands in Pd-catalyzed Buchwald-Hartwig amination reactions was demonstrated with tunable π-acceptor bicyclic bridgehead phosphoramidite (briphos) ligands. The catalytic activity of NHC-Pd-L (L = phosphorus ligand) precatalysts depends on the electronic properties of L. A NHC-Pd-L catalyst with an N-cyclohexyl-substituted briphos ligand was found to be highly efficient. A series of C-N bond coupling reactions between primary or secondary amines and aryl chlorides were performed with high yields under mild reaction conditions.
Ortho, ortho′-Substituted KITPHOS monophosphines: Highly efficient ligands for palladium-catalyzed C-C and C-N bond formation
Doherty, Simon,Knight, Julian G.,McGrady, John P.,Ferguson, Alexandra M.,Ward, Nicholas A. B.,Harrington, Ross W.,Clegg, William
supporting information; experimental part, p. 201 - 211 (2010/06/20)
ortho, ortho′-Substitution of the phosphinoalkyne-derived aryl ring in KITPHOS (11-dicyclohexylphosphino-12-phenyl-9,10-ethenoanthracene) monophosphines enhances the performance of this class of ligand in palladium-catalyzed Suzuki-Miyaura cross-couplings and BuchwaldHartwig aminations, compared with their unsubstituted and mono-substituted counterparts. An alternative complementary synthesis of KITPHOS monophosphines has been developed and two new members of this family, 2,6-Me2-KITPHOS [11-dicyclohexylphosphino-12-(2,6-dimethylphenyl)-9,10-ethenoanthracene] and 2,6-(MeO)2-KITPHOS [11-dicyclohexylphosphino-12-(2,6-dimethoxyphenyl)-9,10-ethenoanthracene], have been prepared; palladium complexes of both are highly efficient catalysts for C - C and C - N bond formation with a range of electron-rich and electron-poor aromatic chlorides as well as heteroaryl chlorides.
Scope and Limitations of the Pd/BINAP-Catalyzed Amination of Aryl Bromides
Wolfe, John P.,Buchwald, Stephen L.
, p. 1144 - 1157 (2007/10/03)
Mixtures of Pd2(dba)3 or Pd(OAc)2 and BINAP catalyze the cross-coupling of amines with a variety of aryl bromides. Primary amines are arylated in high yield, and certain classes of secondary amines are also effectively transformed. The process tolerates the presence of several functional groups including methyl and ethyl esters, enolizable ketones, and nitro groups provided that cesium carbonate is employed as the base. Most reactions proceed to completion with 0.5-1.0 mol % of the palladium catalyst; in some cases, catalyst levels as low as 0.05 mol % Pd may be employed. Reactions are considerably faster if Pd(OAc)2 is employed as the precatalyst, and the order in which reagents are added to the reaction has a substantial effect on reaction rate. It is likely that the catalytic process proceeds via bis(phosphine)palladium complexes as intermediates. These complexes are less prone to undergo undesirable side reactions which lead to diminished yields or catalyst deactivation than complexes of the corresponding monodentate triarylphosphines.
