Stereoselective Alkylations in Rigid Systems. Effect of Remote Substituents on π-Facial Additions to Lactam Enolates. Stereoelectronic and Steric Effects
作者:A. I. Meyers、Mark A. Seefeld、Bruce A. Lefker、James F. Blake、Paul G. Williard
DOI:10.1021/ja980614s
日期:1998.8.1
of the alkylation of their enolates shows a high degree of endo or exo entry, depending upon certain substituents and their positions in the lactams. The suggested reasons for the exo or endo selectivity for alkylation were determined to be purely electronic or purely steric in certain instances. The results of the selectivity study now allow the asymmetric synthesis of various ketones, acids, and pyrrolidines
一系列手性双环内酰胺已经通过实验和从头分子轨道计算进行了研究。其烯醇化物烷基化的面部选择性显示出高度的内或外进入,这取决于某些取代基及其在内酰胺中的位置。在某些情况下,烷基化的外向或内向选择性的建议原因被确定为纯电子或纯空间的。选择性研究的结果现在允许基于所用内酰胺的选择以任一对映体形式不对称合成各种酮、酸和吡咯烷。