26164-26-1Relevant articles and documents
Enantioselective carboxylation of α-methoxybenzyllithium generated via asymmetric lithiation with a t-BuLi/chiral bis(oxazoline) complex
Komine, Nobuyuki,Wang, Lan-Fang,Tomooka, Katsuhiko,Nakai, Takeshi
, p. 6809 - 6812 (1999)
Treatment of benzyl methyl ether with a t-BuLi/chiral bis(oxazoline) complex followed by carboxylation is shown to afford α-methoxy phenylacetic acid in high % ee (up to 95%). The asymmetric induction was proved to occur at the post-lithiation step.
The first asymmetric catalytic halo aldol reaction of β-iodo allenoates with aldehydes by using chiral salen catalyst
Chen, Dianjun,Guo, Li,Kotti, S. R. S. Saibabu,Li, Guigen
, p. 1757 - 1762 (2005)
The first asymmetric catalytic halo aldol reaction of β-iodo allenoates with aldehydes was established. The reaction was successfully achieved by using (R,R)-SalenAlCl as the chiral catalyst and LiI as an additive at 0°C in dichloromethane. Moderate to good yields and up to 62% ee were obtained. The new system showed a good substrate scope in which both aromatic aldehydes and aliphatic aldehydes can be employed. The reaction provided the first catalytic and enantioselective approach to chiral β-iodo Baylis-Hillman ester adducts.
The Synthesis of Chiral α-Aryl α-Hydroxy Carboxylic Acids via RuPHOX-Ru Catalyzed Asymmetric Hydrogenation
Guo, Huan,Li, Jing,Liu, Delong,Zhang, Wanbin
, p. 3665 - 3673 (2017/09/11)
A ruthenocenyl phosphino-oxazoline-ruthenium complex (RuPHOX?Ru) catalyzed asymmetric hydrogenation of α-aryl keto acids has been successfully developed, affording the corresponding chiral α-aryl α-hydroxy carboxylic acids in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 5000 S/C) and the resulting products can be transformed to several chiral building blocks, biologically active compounds and chiral drugs. (Figure presented.).
Effect of the concentration of organic modifier in an aqueous-ethanol mobile phase on the chromatographic retention and thermodynamic characteristics of the adsorption of enantiomers of α-phenylcarboxylic acids on silica gel with immobilized eremomycin antibiotic
Blinov,Reshetova
, p. 1778 - 1784 (2014/11/08)
Regularities of the chromatographic retention and thermodynamics of the adsorption of enantiomers of α-phenylcarboxylic acids on a chiral stationary phase with immobilized macrocyclic antibiotic eremomycin under conditions of reversed-phase liquid chromatography with aqueous-ethanol mobile phases are studied. Relationships between the retention characteristics of the acids, the enantioselectivity of their separation, and the concentration of organic modifier in the mobile phase are found. It is shown that the sterical structure of substituents on the chiral atoms of the acids affect the mechanism of retention. The compensation effect in the studied systems is considered.