Aix Marseille Univ, CNRS Centrale Marseille, iSm2, UMR 7313, 52 Av. Escadrille Normandie Niemen, 13013, Marseille, France.
Chemistry. 2022 Nov 25;28(66):e202202206. doi: 10.1002/chem.202202206. Epub 2022 Sep 26.
The stereoselective copper-mediated hydroxylation of intramolecular C-H bonds from tridentate ligands is reinvestigated using DFT calculations. The computational study aims at deciphering the mechanism of C-H hydroxylation obtained after reaction of Cu(I) precursors with dioxygen, using ligands bearing either activated (L ) or non-activated (L ) C-H bonds. Configurational analysis allows rationalization of the experimentally observed regio- and stereoselectivity. The computed mechanism involves the formation of a side-on peroxide species (P) in equilibrium with the key intermediate bis-(μ-oxo) isomer (O) responsible for the C-H activation step. The P/O equilibrium yields the same activation barrier for the two complexes. However, the main difference between the two model complexes is observed during the C-H activation step, where the complex bearing the non-activated C-H bonds yields a higher energy barrier, accounting for the experimental lack of reactivity of this complex under those conditions.
使用密度泛函理论（DFT）计算重新研究了手性铜介导的三齿配体中环内 C-H 键的立体选择性羟化反应。该计算研究旨在通过与氧气反应的 Cu（I）前体，使用带有活化（L）或非活化（L）C-H 键的配体，来解释 C-H 羟化反应的机制。构象分析允许对实验观察到的区域和立体选择性进行合理化。计算出的机制涉及到形成侧过氧化物物种（P）与关键中间体双（μ-氧）异构体（O）的平衡，后者负责 C-H 活化步骤。P/O 平衡对两个配合物产生相同的活化能垒。然而，在 C-H 活化步骤中，两个模型配合物之间的主要区别被观察到，其中带有非活化 C-H 键的配合物产生更高的能量垒，这解释了在这些条件下该配合物缺乏反应性的实验事实。
