In a conceptually different approach, highly stereoselective 2-oxonia-Cope rearrangement reactions between rationally designed nonracemic vinylogous aldolation synthons and aldehydes are described to provide δ-hydroxy-α,β-unsaturated esters with excellent enantioselectivities and, for the first time, unprecedented Z- and E-selectivities without the regioselectivity issue.
在概念上不同的方法中,描述了合理设计的非外消旋
乙烯基醛醇缩合合成子与醛之间的高度立体选择性的2- oxonia- Cope重排反应,可提供具有出色对映选择性的δ-羟基-α,β-不饱和酯,并且是前所未有的Z -和E-选择性没有区域选择性的问题。