Rh/Wudaphos-Catalyzed Asymmetric Hydrogenation of Sodium α-Arylethenylsulfonates: A Method to Access Chiral α-Arylethylsulfonic Acids
A highly enantioselective hydrogenation of various sodium α-arylethenylsulfonates catalyzed by Rh/chiral ferrocenyl bisphosphorus ligand (Wudaphos) was successfully developed to construct a series of chiral α-arylethylsulfonic acids in the presence of CF3SO3H with full conversion and good to excellent enantioselectivity (>99% conversion, up to 96% ee) under mild reaction conditions for the first time. Moreover, the control experiment results showed that the non-covalent ion pair interaction between the α-arylethenylsulfonic acid and the Wudaphos ligand plays an important role in this asymmetric hydrogenation system.
Efficient asymmetric synthesis of α-alkylated benzylic methyl sulfonates
The first highly efficient auxiliary-controlled synthesis of various α-substituted sulfonic acid derivatives is described. Alkyl or aryl halides were reacted with lithiated benzylic sulfonic esters bearing 1,2:5,6-di-O-isopropylidene-α-d-allofuranose as a
Enders, Dieter,Vignola, Nicola,Berner, Otto M.,Harnying, Wacharee
p. 3231 - 3243
(2007/10/03)
Dutch Resolution: Separation of enantiomers with families of resolving agents. A status report
Dutch Resolution is the term given to the use of mixtures (families) of resolving agents in classical resolutions. In this status report an overview is given of the latest results and new (possible) families of resolving agents are introduced. The concept of families is discussed as well as the factors that come into play on use of families. Practical aspects of Dutch Resolution in particular and resolutions in general are discussed.
Kellogg, Richard M.,Nieuwenhuijzen, Jose W.,Pouwer,Vries, Ton R.,Broxterman, Quirinus B.,Grimbergen, Reinier F.P.,Kaptein, Bernard,La Crois, Rene M.,De Wever, Ellen,Zwaagstra, Karen,Van Der Laan, Alexander C.
p. 1626 - 1638
(2007/10/03)
The first highly efficient asymmetric synthesis of α-substituted methyl sulfonates
The right choice of sugar auxiliary led to a breakthrough in the first asymmetric α-alkylations of sulfonic acid esters (see scheme). The high asymmetric inductions were reached with 1,2:5,6-di-O-isopropyliden-α-D-allofuranose as the auxiliary group, whic
Enders, Dieter,Vignola, Nicola,Berner, Otto M.,Bats, Jan W.
p. 109 - 111
(2007/10/03)
More Articles about upstream products of 86963-40-8