Transition Structure Geometries for Transfers of Neutral and Anionic Nitrogen to Lithiated Carbanions
作者:Peter Beak、Kathryn Conser Basu、James J. Li
DOI:10.1021/jo990509g
日期:1999.7.1
reaction via an oriented ion pair. Attempted endocyclic restriction tests for transfers of formally anionic nitrogen with 32 and 33 were not successful. Reactions of n-butyl, s-butyl and tert-butyllithium reagents with 16, 23, 30, 31, and 36-38 generally afford higher yields with increasing substitution at the carbon of the organolithium reagent and with decreasing substitution adjacent to the nitrogen
已经研究了有机锂物种在中性和阴离子氮处亲核取代的几何结构。9 到 10 的分子内转化的证明提供了内环限制性测试,该测试支持用于氮转移的三角双锥过渡结构。在氮转移过程中缺乏 12a-18O 的同位素扰乱被用来排除通过定向离子对的反应。尝试用 32 和 33 转移形式上的阴离子氮的内环限制性测试没有成功。正丁基、仲丁基和叔丁基锂试剂与 16、23、30、31 和 36-38 的反应通常会提供更高的产率,同时有机锂试剂碳上的取代基增加,而与氮原子相邻的取代基减少胺化试剂。