Analyzing Site Selectivity in Rh<sub>2</sub>(esp)<sub>2</sub>-Catalyzed Intermolecular C–H Amination Reactions
作者:Elizabeth N. Bess、Ryan J. DeLuca、Daniel J. Tindall、Martins S. Oderinde、Jennifer L. Roizen、J. Du Bois、Matthew S. Sigman
DOI:10.1021/ja5015508
日期:2014.4.16
Predicting site selectivity in C–H bond oxidation reactions involving heteroatom transfer is challenged by the small energetic differences between disparate bond types and the subtle interplay of steric and electronic effects that influence reactivity. Herein, the factors governing selective Rh2(esp)2-catalyzed C–H amination of isoamylbenzene derivatives are investigated, where modification to both
在涉及杂原子转移的 C-H 键氧化反应中预测位点选择性受到不同键类型之间小的能量差异以及影响反应性的空间和电子效应的微妙相互作用的挑战。在此,研究了控制异戊基苯衍生物的选择性 Rh2(esp)2 催化 C-H 胺化的因素,其中显示对氮源、氨基磺酸酯和底物的修饰会影响异构产物比率。线性回归数学模型用于定义一种关系,该关系将 IR 拉伸参数和 Hammett σ+ 值等同于苄基与叔 C-H 胺化的微分自由能。该模型为新型氨基磺酸酯的开发提供了依据,该酯可提供最高的苄基到叔位点选择性 (9.5: