Direct, Enantioselective Iridium-Catalyzed Allylic Amination of Racemic Allylic Alcohols
作者:Marc Lafrance、Markus Roggen、Erick M. Carreira
DOI:10.1002/anie.201108287
日期:2012.4.2
The direct route: Iridium‐catalyzed direct conversion of branched allylicalcohols into enantioenriched branched primary allylic amines is highly regio‐ and enantioselective (see scheme; coe=cyclooctene).
Stereospecific Substitution of Allylic Alcohols To Give Optically Active Primary Allylic Amines: Unique Reactivity of a (P,alkene)Ir Complex Modulated by Iodide
作者:Markus Roggen、Erick M. Carreira
DOI:10.1021/ja105271z
日期:2010.9.1
A stereospecificallylic amination of unactivated secondary (secondary)-allylic alcohols is reported. The primary (primary)-allylic amine can be isolated directly or protected in situ. Spectroscopic studies have shed light on the structure of the catalytically activeIr x (P,olefin)2I complex.
报道了未活化的仲(仲)烯丙醇的立体有择烯丙胺化。伯(伯)烯丙胺可以直接分离或原位保护。光谱研究揭示了具有催化活性的 Ir x (P,烯烃)2I 复合物的结构。
Asymmetric synthesis of α- and β-amino acids by diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl)imines
作者:Raquel Almansa、Juan F. Collados、David Guijarro、Miguel Yus
DOI:10.1016/j.tetasy.2010.03.046
日期:2010.6
The diastereoselective addition of triorganozincates to (R)-N-(tert-butanesulfinyl)imines has been used as a key step to achieve the synthesis of highly enantiomerically enriched N-protected alpha- and beta-amino acids. Desulfinylation of the addition products followed by benzoylation of the nitrogen atom of the obtained primary amines and oxidation of one of the substituents on the carbon atom connected to the nitrogen complete the sequence. Using the same configuration in the sulfinyl chiral auxiliary, alpha-amino acids with the (R) or the (S) configuration can be prepared by choosing the proper combination of imine and organozincate. alpha,alpha-Disubstituted alpha-amino esters with high enantiomeric purity can also be prepared when a-imino esters are the starting substrates. (C) 2010 Elsevier Ltd. All rights reserved.