Novel AC regioisomer cationic cyclodextrins have been successfully prepared with azide/alkyne click chemistry. The clicked CDs were explored for the enantioseparation of acidic racemates in capillary electrophoresis.
An effective kinetic resolution of racemic α-arylpropanoic acids, α-arylbutanoic acids, and β-substituted-α-arylpropanoic acids with bis(9-phenanthryl)methanol as a new achiral nucleophile in the asymmetric esterification using carboxylic anhydrides and the acyl-transfer catalyst
kinetic resolution of racemic α-arylalkanoic acids with achiral alcohols is described. It was determined that bis(9-phenanthryl)methanol is a suitable nucleophile which reacts with the intermediary mixed anhydrides generated from aromatic anhydrides with α-arylpropanoic acids or β-substituted-α-arylpropanoic acids in the presence of (+)-benzotetramisole to produce the corresponding opticallyactive esters
Iridium-Catalyzed Enantioselective Hydrogenation of α,β-Unsaturated Carboxylic Acids with Tetrasubstituted Olefins
作者:Song Song、Shou-Fei Zhu、Yu Li、Qi-Lin Zhou
DOI:10.1021/ol401593a
日期:2013.7.19
A highly efficient asymmetrichydrogenation of α,β-unsaturatedcarboxylicacids with tetrasubstituted olefin catalyzed by chiral spiro iridium complexes has been developed for the preparation of chiral α-substituted carboxylicacids in excellent enantioselectivities (up to 99% ee).