Tertiary alkylamines can coordinate palladium salts and direct C–H activation reactions. However, these tertiary alkylamines can suffer from decomposition through oxidative pathways. This report describes the DFT analysis of acyclic and cyclic tertiary alkylamines with respect to C–H bond cleavage through either γ-C(sp³)–H activation on the exo N-substituent or β-H elimination at the endocyclic position. The study assesses the role of an N-acetyl amino acid ligand in suppressing the β-H elimination pathway. Experiments using tertiary alkylamines with isotopically labeled α-C–D bonds demonstrate the small differences in energy barriers that discern both reaction pathways. Guided by the insights of computational studies on methyl and strained methylene γ-C–H activation in tertiary alkylamines, we report a successful methine γ-C–H activation to construct ring-strained quaternary centers through intermolecular C–H arylation.

中文翻译：

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Pd 催化的 C-H 活化与 β-H 消除：对叔烷基胺反应性的实验和计算见解


叔烷基胺可以配位钯盐并直接 C-H 活化反应。然而，这些叔烷基胺会通过氧化途径分解。本报告描述了无环和环叔烷基胺的 DFT 分析，通过外切 N 取代基上的 γ-C（sp³）-H 活化或内环位置的 β-H 消除进行 C-H 键裂解。该研究评估了 N-乙酰氨基酸配体在抑制 β-H 消除途径中的作用。使用具有同位素标记的 α-C-D 键的叔烷基胺的实验表明，区分两种反应途径的能垒存在微小差异。在对叔烷基胺中甲基和应变亚甲基 γ-C-H 活化的计算研究见解的指导下，我们报道了一种成功的甲嘧啶 γ-C-H 活化，通过分子间 C-H 芳基化构建环应变的四级中心。