Facile Synthesis of Enantioenriched C<sup>γ</sup>-Tetrasubstituted α-Amino Acid Derivatives via an Asymmetric Nucleophilic Addition/Protonation Cascade
作者:Shu-Wen Duan、Jing An、Jia-Rong Chen、Wen-Jing Xiao
DOI:10.1021/ol200550y
日期:2011.5.6
An asymmetric nucleophilic addition/protonation reaction of 3-substituted oxindoles and ethyl 2-phthalimidoacrylate has been described. This strategy can give direct access to Cγ-tetrasubstituted α-amino acid derivatives bearing 1,3-nonadjacent stereocenters with up to 98% yield, 94:6 dr, and >99% ee. Dual activation is proposed in the transition state, and the opposite enantiomers can be obtained
已经描述了3-取代的羟吲哚和2-邻苯二甲酰亚胺基丙烯酸乙酯的不对称亲核加成/质子化反应。这种策略可以给予至C直接访问γ -tetrasubstitutedα氨基酸衍生物轴承1,3-不相邻的立体中心具有高达98%的收率,94:6 DR,和> 99%ee的。提出了在过渡态下的双重活化,并且可以简单地通过将辛可尼丁衍生的催化剂改变为辛可宁类似物来获得相反的对映异构体。