Organocatalytic enantio- and diastereoselective 1,3-dipolar cycloaddition between alanine-derived ketonitrones and E-crotonaldehyde: efficiency and full stereochemical studies
摘要:
Highly enantio- and exo-selective 1,3-dipolar cycloadditions of alanine-derived ketonitrones to E-crotonaldehyde could be realized in a good yield by the use of a chiral imidazolidinone salt without the addition of water. The origin of the stereoselectivity in the reaction was discussed and the absolute configuration of the cycloadduct determined unambiguously. (C) 2012 Elsevier Ltd. All rights reserved.
Organocatalytic enantio- and diastereoselective 1,3-dipolar cycloaddition between alanine-derived ketonitrones and E-crotonaldehyde: efficiency and full stereochemical studies
作者:Khalid B. Selim、Anne Beauchard、Jérôme Lhoste、Arnaud Martel、Mathieu Y. Laurent、Gilles Dujardin
DOI:10.1016/j.tetasy.2012.11.010
日期:2012.12
Highly enantio- and exo-selective 1,3-dipolar cycloadditions of alanine-derived ketonitrones to E-crotonaldehyde could be realized in a good yield by the use of a chiral imidazolidinone salt without the addition of water. The origin of the stereoselectivity in the reaction was discussed and the absolute configuration of the cycloadduct determined unambiguously. (C) 2012 Elsevier Ltd. All rights reserved.
Asymmetric Access to α-Substituted Functional Aspartic Acid Derivatives by a [3+2] Strategy Employing a Chiral Dienophile
作者:Kawther Ben Ayed、Anne Beauchard、Jean-François Poisson、Sandrine Py、Mathieu Y. Laurent、Arnaud Martel、Houcine Ammar、Souhir Abid、Gilles Dujardin
DOI:10.1002/ejoc.201301739
日期:2014.5
NH-isoxazolidine, the absolute configuration of which was established by X-ray crystallography. N-Protection and N–O cleavage of this isoxazolidine gave enantioenriched quaternary aspartate derivatives bearing functionalized side chains.