(<i>S</i>,<i>S</i>)-(<i>+</i>)-Pseudoephedrine as Chiral Auxiliary in Asymmetric Aza-Michael Reactions. Unexpected Selectivity Change when Manipulating the Structure of the Auxiliary
作者:Juan Etxebarria、Jose L. Vicario、Dolores Badia、Luisa Carrillo、Nerea Ruiz
DOI:10.1021/jo051207j
日期:2005.10.1
the structure of the chiral auxiliary, which has allowed a diastereodivergent procedure to be set up for performing asymmetric aza-Michael reactions using the same chirality source. Finally, the adducts obtained in the asymmetric aza-Michael reaction have proven to be very versatile synthetic intermediates in the preparation of other interesting compounds such as β-amino esters, γ-amino alcohols, and
金属苄酰胺与手性氨基醇衍生的α,β-不饱和酰胺的不对称aza-Michael反应(S,S)-(+)-伪麻黄碱已被详细研究。已经对最重要的实验参数(溶剂,温度,亲核体结构,添加剂的影响)进行了深入研究,表明该反应通常以良好的收率和非对映选择性进行,尽管必须根据取代条件修改实验条件共轭受体的模式。另外,在操纵手性助剂的结构时,观察到非常有趣的面部选择性反转,这允许建立非对映发散程序,以使用相同的手性来源进行不对称的aza-Michael反应。最后,