36617-88-6Relevant academic research and scientific papers
Nickel-catalyzed asymmetric hydrovinylation using lewis acid activation
Lassauque, Nicolas,Francio, Giancarlo,Leitner, Walter
, p. 3199 - 3202 (2009)
A broad range of commercially available Lewis acids were investigated for their ability to activate and regulate nickel catalysts for asymmetric hydrovinylation processes using styrene as model substrate and ligand (R a,Sc,Sc/s
New Chiral Phosphine Ligands Containing (η6-Arene)chromium and Catalytic Asymmetric Cross-Coupling Reactions
Uemura, Motokazu,Miyake, Ryuta,Nishimura, Hikaru,Matsumoto, Yonetatsu,Hayashi, Tamio
, p. 213 - 216 (1992)
New chiral monophosphine ligands 2-4 containing (η6-arene)chromium were prepared via the stereoselective ortho-lithiation od ((R)-N,N-dimethyl-1-phenylethylamine)-Cr(CO)3 (1).Asymmetric cross-coupling of 1-phenylethylmagnesium or zinc reagent with vinyl bromides in the presence of palladium or nickel catalysts complexed with the chiral (η6-arene)chromium ligands gave the coupling products of up to 61 percentee.
Phosphoramidite quinaphos-type ligands for highly selective Ni-catalysed asymmetric C-C bond forming reactions
Diez-Holz, Christiane J.,Boeing, Christian,Francio, Giancarlo,Hoelscher, Markus,Leitner, Walter
, p. 2995 - 3002 (2007)
Monodentate quinaphos phosphoramidites bearing different substituents in the 2-position of the 1,2-dihydroquinoline backbone were synthesised and characterised. Computational, NMR spectroscopic and X-ray crystallographic methods were used for the elucidat
Palladium-catalysed Enantioselective Grignard Cross Coupling with Use of a new Ferrocenylaminophosphine Ligand
Jedlicka, Brigitte,Kratky, Christoph,Weissensteiner, Walter,Widhalm, Michael
, p. 1329 - 1330 (1993)
A new ferrocenylaminophosphine ligand, cyclopentadienyl(7-dimethylamino-1-diphenylphosphino-4,5,6,7-tetrahydroindenyl)iron (ptfa), and its palladium dichloride complex have been synthesised, structurally characterised by X-ray analysis of the palladium complex, and shown to be effective in the enantioselective Grignard cross coupling reaction of phenethylmagnesium chloride and vinyl bromide giving 3-phenylbut-1-ene with 79percent enantiomeric excess.
ASYMMETRISCHE KATALYSEN. VI. NiCl2(-)NORPHOS-KATALYSIERTE CROSS-COUPLING-REAKTION VON 1-PHENYLETHYL-GRIGNARD MIT VINYLBROMID
Brunner, H.,Proebster, M.
, p. C1 - C3 (1981)
In the cross-coupling of racemic 1-phenylethyl-Grignard with vinylbromide catalyzed by NiCl2(-)Norphos, (S)-3-phenyl-1-butene is obtained in 95percent chemical yield and 67percent optical yield.
Preparation and use of chiral ferrocenylphosphines containing new alkyl substituents on the ferrocenylmethyl position
Ohno,Yamane,Hayashi,Oguni,Hayashi
, p. 2495 - 2502 (1995)
New homochiral ferrocenylphosphines, (Et-PPFA 5a), (Et-BPPFA 6a), and (Bu-BPPFA 6b), containing an ethyl or butyl group on the ferrocenylmethyl position were prepared by way of stereoselective ortho lithiation of (R)-N,N-dimethyl-1-ferrocenylpropylamine (4a) or its pentylamine analogue 4b, the lithiation proceeding with high (>99%) diastereoselectivity. Ethyl-substituted ferrocenylmonophosphine (Et-PPFA 5a) and ferrocenylbisphosphine (Et-BPPFA 6a) were found to be more effective as chiral ligands than the methyl-substituted ferrocenylphosphines, PPFA 1 and BPPFA 2, respectively, for some catalytic asymmetric reactions including nickel-catalyzed cross-coupling and palladium-catalyzed allylic silylation.
P-Chiral Monophosphorus Ligands for Asymmetric Copper-Catalyzed Allylic Alkylation
Xiong, Wenrui,Xu, Guangqing,Yu, Xinhong,Tang, Wenjun
, p. 4003 - 4013 (2019/06/24)
Asymmetric copper-catalyzed allylic alkylation between allyl bromides and alkyl Grignard reagents using a P-chiral monophosphorus ligand is described. A range of terminal olefins bearing tertiary or quaternary carbon centers were formed in good branched/linear selectivities and excellent enantioselectivities at copper loadings as low as 0.5 mol %.
Low-Pressure Cobalt-Catalyzed Enantioselective Hydrovinylation of Vinylarenes
Movahhed, Sohajl,Westphal, Julia,Dindaro?lu, Mehmet,Falk, Anna,Schmalz, Hans-Günther
supporting information, p. 7381 - 7384 (2016/05/24)
An efficient and practical protocol for the enantioselective cobalt-catalyzed hydrovinylation of vinylarenes with ethylene at low (1.2 bar) pressure has been developed. As precatalysts, stable [L2CoCl2] complexes are employed that are activated in situ with Et2AlCl. A modular chiral TADDOL-derived phosphine-phosphite ligand was identified that allows the conversion of a broad spectrum of substrates, including heterocyclic vinylarenes and vinylferrocene, to smoothly afford the branched products with up to 99 % ee and virtually complete regioselectivity. Even polar functional groups, such as OH, NH2, CN, and CO2R, are tolerated.
Neutral and Cationic Palladium Complexes of P-Stereogenic Phosphanes Bearing a Heterocyclic Substituent
Clavero, Pau,Grabulosa, Arnald,Rocamora, Mercè,Muller, Guillermo,Font-Bardia, Mercè
, p. 4216 - 4225 (2016/09/16)
The coordination chemistry of 13 optically pure P-stereogenic diarylmonophosphanes P(Het)PhR [Het = 4-dibenzofuranyl (DBF), 4-dibenzothiophenyl (DBT), 4-dibenzothiophenyl S,S-dioxide (DBTO2) and 1-thianthrenyl (TA); R = OMe, Me, iPr, Fc (ferroc
Improvements and Applications of the Transition Metal-Free Asymmetric Allylic Alkylation using Grignard Reagents and Magnesium Alanates
Grassi, David,Alexakis, Alexandre
supporting information, p. 3171 - 3186 (2015/11/03)
Two new N-heterocyclic carbene (NHC) ligands have been synthesized and employed in the transition metal-free asymmetric allylic alkylation (AAA) mediated by Grignard reagents and magnesium alanates. The employment of these ligands showed high yields and improved regio- and enantioselectivity in the formation of tertiary and quaternary stereocenters. Moreover, the low catalyst loading (up to 0.3 mol%) and high scalability (up to 10 mmol) of this improved methodology provide a convenient access to biologically active compounds and synthetically valuable intermediates.
