New Zinc(II)-Based Catalyst for Asymmetric Azomethine Ylide Cycloaddition Reactions
摘要:
A new chiral aziridino alcohol ligand for zinc(II)-catalyzed azomethine ylide cycloadditions is described. In the presence of this catalyst, N-arylidene glycine methyl esters react with a variety of dipolarophiles to give substituted pyrrolidines in very good to excellent chemical yields and up to 95% ee. The absolute sense of asymmetric induction appears to be dipolarophile-dependent.
Stereocontrolled 1,3-dipolar cycloadditions using Oppolzer's camphor sultam as the chiral auxiliary for carbonyl stabilized azomethine ylides
作者:Philip Garner、Özdemir Dogan、Wiley J. Youngs、Vance O. Kennedy、John Protasiewicz、Rebecca Zaniewski
DOI:10.1016/s0040-4020(00)00998-4
日期:2001.1
Two complementary approaches to substituted pyrrolidines via stereocontrolled 1,3-dipolar cycloadditionreactions of chiral azomethine ylides are described. In one approach, chiral azomethine ylides were generated by thermolysis of aziridine carboxylate sultams and trapped with a variety of dipolarophiles to give good yields of the corresponding cycloadducts. In the second approach, chiral azomethine