Using Heteroaryl-lithium Reagents as Hydroxycarbonyl Anion Equivalents in Conjugate Addition Reactions with (<i>S</i>,<i>S</i>)-(+)-Pseudoephedrine as Chiral Auxiliary; Enantioselective Synthesis of 3-Substituted Pyrrolidines
作者:Beatriz Alonso、Marta Ocejo、Luisa Carrillo、Jose L. Vicario、Efraim Reyes、Uxue Uria
DOI:10.1021/jo302438k
日期:2013.1.18
of hydroxycarbonyl anion equivalents to α,β-unsaturated carboxylic acid derivatives using (S,S)-(+)-pseudoephedrine as chiral auxiliary, making use of the synthetic equivalence between the heteroaryl moieties and the carboxylate group. This protocol has been applied as key step in the enantioselective synthesis of 3-substituted pyrrolidines in which, after removing the chiral auxiliary, the heteroaryl
我们已经开发出一种有效的方案,可以使用(S,S)-(+)-伪麻黄碱作为手性助剂,利用杂芳基部分和羧酸酯基团之间的合成等价物。该方案被用作3-取代的吡咯烷的对映选择性合成中的关键步骤,其中在除去手性助剂后,杂芳基部分被转化为羧酸酯基团,随后被还原和双亲核取代。或者,也可以通过将有机锂试剂与衍生自相同手性的α,β,γ,δ-不饱和酰胺的区域和非对映选择性共轭加成,来获得相同类型的杂环骨架,但具有相反的绝对构型。辅助,然后手性辅助去除,臭氧分解和还原胺化/分子内亲核取代序列。