85711-06-4Relevant academic research and scientific papers
New chiral ammonium salt hosts derived from amino acids: Very efficient optical resolution of 2,2′-dihydroxy-1,1′-binaphthyl by complexation with these host compounds
Toda, Fumio,Tanaka, Kenya
, p. 1087 - 1088 (1997)
Chiral ammonium salt hosts are prepared from amino acids by transformation of their NH2 and CO2H groups into Me3N+Br- and CH2OH groups, respectively, via three simple reaction steps; by complexation with these hosts, 2,2′-dihydroxy-1,1′-binaphthyl is resolved very efficiently.
Synthesis and utilization of trifluoromethylated amino alcohol ligands for the enantioselective Reformatsky reaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine
Xu, Xiu-Hua,Qiu, Xiao-Long,Qing, Feng-Ling
, p. 7353 - 7361 (2008/12/20)
A series of trifluoromethylated amino alcohol ligands, which had been designed and conveniently prepared, were successfully applied in the enantioselective Reformatsky reaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine, respectively. The influence of the substituents on C-3 position and the amino moiety on the enantioselectivity has been carefully investigated. In the best cases, ligand 1b exhibited good selectivity for the enantioselective Reformatsky reaction in 86% ee and ligand 12d provided excellent enantioselectivity in the addition of diethylzinc to N-(diphenylphosphinoyl)imine with 95% ee.
Chiral (β-Aminoalkyl)phosphines. Highly Efficient Phosphine Ligands for Catalytic Asymmetric Grignard Cross-Coupling
Hayashi, Tamio,Konishi, Mitsuo,Fukushima, Motoo,Kanehira, Koichi,Hioki, Takeshi,Kumada, Makoto
, p. 2195 - 2202 (2007/10/02)
New chiral (β-aminoalkyl)phosphines, RCH(NMe2)CH2PPh2 , were prepared by starting with optically active amino acids.The phosphines were used as ligands for nickel-catalyzed asymmetric cross-coupling of 1-arylethyl Grignard reagents (ArMeCHMgCl) with vinyl bromide.Coupling products of over 70percent enantiomeric excess (ee) were obtained in the reaction with the ligand Phephos, Valphos, Ilephos, PhGlyphos, ChGlyphos, or t-Leuphos.A mechanism involving complexation of the magnesium atom in the Grignard reagent with the amino group on the (β-aminoalkyl)phosphine ligand is proposed to account for the high stereoselectivity.The asymmetric cross-coupling was applied to the synthesis of optically active 2-arylpropionic acids.
