627503-87-1Relevant academic research and scientific papers
Highly Enantioselective Ferrocenyl Palladacycle-Acetate Catalysed Arylation of Aldimines and Ketimines with Arylboroxines
Schrapel, Carmen,Frey, Wolfgang,Garnier, Delphine,Peters, René
supporting information, p. 2448 - 2460 (2017/02/23)
Benzylic N-substituted stereocenters constitute a frequent structural motif in drugs. Their highly enantioselective generation is hence of technical importance. An attractive strategy is the arylation of imines with organoboron reagents. Chiral Rh complexes have reached a high level of productivity for this reaction type. In this article we describe that an electron rich PdIIcatalyst also performs well in the arylation of aldimines, comparable to the best Rh catalysts. The ferrocenyl palladacycle-acetate catalyst allows for a broad substrate scope and very high enantioselectivities. Commonly observed side reactions like aryl–aryl homocouplings and imine hydrolysis could be blocked. Mechanistic studies implicate that a) the acetate ligand is crucial for transmetallation, b) the active catalyst is most likely a palladacycle-OAc monomer, c) the rate limiting step is probably the product release. By added KOAc the arylation could also be applied to ketimines.
Palladium-Catalyzed Enantioselective Three-Component Synthesis of α-Substituted Amines
Beisel, Tamara,Manolikakes, Georg
supporting information, p. 3162 - 3165 (2015/06/30)
The first general palladium-catalyzed, enantioselective three-component synthesis of α-arylamines starting from sulfonamides, aldehydes, and arylboronic acids has been developed. These reactions generate a wide array of α-arylamines with high yields and e
Exogenous-Base-Free Palladacycle-Catalyzed Highly Enantioselective Arylation of Imines with Arylboroxines
Schrapel, Carmen,Peters, Ren
supporting information, p. 10289 - 10293 (2015/09/01)
Enantiomerically pure benzylic amines are important for the development of new drugs. A readily accessible planar-chiral ferrocene-derived palladacycle is shown to be a highly efficient catalyst for the formation of N-substituted benzylic stereocenters; t
Chiral N-Heterocyclic Carbene Ligands Bearing a Pyridine Moiety for the Copper-Catalyzed Alkylation of N-Sulfonylimines with Dialkylzinc Reagents
Soeta, Takahiro,Ishizaka, Tomohiro,Tabatake, Yuta,Ukaji, Yutaka
supporting information, p. 16773 - 16778 (2016/02/18)
Amino acid-derived chiral imidazolium salts, each bearing a pyridine ring, were developed as N-heterocyclic carbene ligands. The copper-catalyzed asymmetric alkylation of various N-sulfonylimines with dialkylzinc reagents in the presence of these chiral imidazolium salts afforded the corresponding alkylated products with high enantioselectivity (up to 99 % ee). The addition of HMPA to the reaction mixture as a co-solvent is critical in terms of chemical yield and enantioselectivity. A wide range of N-sulfonylimines and dialkylzinc reagents were found to be applicable to this reaction. Amino acid-derived chiral imidazolium salts, each bearing a pyridine ring, were developed as N-heterocyclic carbene ligands. The copper-catalyzed asymmetric alkylation of various N-sulfonylimines with dialkylzinc reagents in the presence of these chiral imidazolium salts afforded the corresponding alkylated products with high enantioselectivity (up to 99 % ee; see scheme). A wide range of N-sulfonylimines and dialkylzinc reagents were found to be applicable to this reaction.
ortho-metalation of enantiopure aromatic sulfoxides and stereocontrolled addition to imines
Le Fur, Nicolas,Mojovic, Ljubica,Ple, Nelly,Turck, Alain,Reboul, Vincent,Metzner, Patrick
, p. 2609 - 2616 (2007/10/03)
Enantiopure aromatic (phenyl, naphthyl) and heteroaromatic (pyridyl, quinolyl, diazinyl) sulfoxides have been synthesized by reaction of (5)-tert-butyl tert-butanethiosulfinate with aryl- or heteroaryllithium derivatives. The ortho-directed metalation of
Asymmetric Alkylation of N-Toluenesulfonylimines with Dialkylzinc Reagents Catalyzed by Copper-Chiral Amidophosphine
Soeta, Takahiro,Nagai, Kazushige,Fujihara, Hidetaka,Kuriyama, Masami,Tomioka, Kiyoshi
, p. 9723 - 9727 (2007/10/03)
The synthetic procedure of a chiral amidophosphine ligand 5 bearing two bulky substituents, 2,4,6-trimethylphenylmethyl or 2,4,6-triisopropylphenylmethyl groups, on the pyrrolidine ring was improved by employing the borane-THF reduction of the lactam-alco
Asymmetric Induction in the Reduction of Optically Active N-Alkylidenesulphinamides by Metal Hydrides. A New, Efficient Enantioselective Route to Chiral Amines
Annunziata, Rita,Cinquini, Mauro,Cozzi, Franco
, p. 339 - 344 (2007/10/02)
A series of racemic and optically active N-alkylidenesulphinamides has been prepared and their reduction by metal hydrides studied.The extent of asymmetric synthesis mainly depends on the nature of the reducing species; the best results (up to 92percent of stereoselectivity) are obtained with alkoxy-lithium aluminium hydrides.A new, highly enantioselective synthesis of amines is described.
