Chiral primary amine mediated conjugate addition of branched aldehydes to vinyl sulfone: asymmetric generation of quaternary carbon centers
作者:Qiang Zhu、Yixin Lu
DOI:10.1039/b919549a
日期:——
Novel L-threonine-derived bifunctional organic catalysts containing primary amine and sulfonamide groups were utilized to promote asymmetric conjugateaddition of alpha,alpha-disubstituted aldehydes to 1,1-bis(benzenesulfonyl)ethylene. The adducts with quaternary stereogenic centers adjacent to an aldehyde group were obtained in high yield and with good enantioselectivity.
Facile Synthesis of Bicyclic Amidines and Imidazolines from 1,2-Diamines
作者:Qiang Zhu、Yixin Lu
DOI:10.1021/ol101747n
日期:2010.9.17
A facile synthesis of chiral bicyclic amidines and imidazolines from readily available 1,2-diamines has been developed. The reported synthetic strategy relies on an intramolecular cyclization which involves a carboxylic amide derived imidoyl chloride as a key intermediate and aniline serving as a leaving group.