Stereodivergency in Catalytic Asymmetric Conjugate Addition Reactions of Glycine (Ket)imines
作者:Hun Young Kim、Jian-Yuan Li、Sungkyung Kim、Kyungsoo Oh
DOI:10.1021/ja2100356
日期:2011.12.28
catalytic asymmetric conjugatereactions of glycine (ket)imines with nitroalkenes have been achieved using various chiral catalyst systems derivedfrom a multidentate amino alcohol (1). The stepwise nature of the [3 + 2] cycloaddition reactions of N-metalated azomethine ylides has also been demonstrated by highly enantio- and diastereoselective syntheses of exo-5 and endo-8 from the respective syn-4
Diastereo- and Enantioselective Synthesis of α,γ-Diaminobutyric Acid Derivatives via Cu-Catalyzed Asymmetric Michael Reaction
作者:Qing Li、Chang-Hua Ding、Xue-Long Hou、Li-Xin Dai
DOI:10.1021/ol100060t
日期:2010.3.5
addition of glycine derivatives to nitroalkenes have been developed. The enantioselectivity of ortho-substituted products can be significantly improved by using a new 1,2-P,N-ferrocene ligand L5. The α,γ-diaminoacid derivative was obtained without the loss of optical activity from the adduct.