Conformational control in the SuperQuat chiral auxiliary 5,5-dimethyl-4-iso-propyloxazolidin-2-one induces the iso-propyl group to mimic a tert-butyl group
作者:Steven D. Bull、Stephen G. Davies、Min-Suk Key、Rebecca L. Nicholson、Edward D. Savory
DOI:10.1039/b005419o
日期:——
1
H NMR nOe spectroscopic studies reveal that
conformational control in the enolates of
N-acyl-5,5-dimethyl-4-iso-propyloxazolidin-2-ones ensures
that the stereodirecting effect of its 4-iso-propyl-5,5-dimethyl
functional group affords superior levels of facial selectivity normally
associated with enolates derived from
N-acyl-4-tert-butyloxazolidin-2-ones.
1 H NMR nOe 光谱研究表明,N-酰基-5,5-二甲基-4-异丙基恶唑啉-2-酮烯醇盐的构象控制确保了其 4-异丙基-5,5-二甲基官能团的立体定向效应,从而提供了通常与 N-酰基-4-叔丁基恶唑啉-2-酮烯醇盐相关的卓越的面部选择性。