Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Changchun 130023, P. R. China.
J Org Chem. 2023 Jun 2;88(11):7320-7327. doi: 10.1021/acs.joc.3c00539. Epub 2023 May 11.
The rhodium(III)-catalyzed reaction of aniline derivatives that contain a pyrimidine-directing group with vinylsilanes results in the formation of C3-substituted indoline derivatives. The reaction path and formation of the indoline product with density functional theory calculations were analyzed. This study reveals that the whole catalysis can be characterized in the following stages: (I) C-H activation via concerted metalation deprotonation, (II) 2,1-vinylsilane insertion, (III) deprotonation of the NH amide proton, (IV) the oxidation of Ag, and (V) reductive elimination. These steps are kinetically and thermodynamically feasible for experimental realization under mild conditions, and the insertion step with a barrier of 22.0 kcal/mol should not only be the critical step of regioselectivity but also the rate-determining step during the whole catalysis. Computations reveal that the Ag oxidation can accelerate the reductive elimination step after the formation of natural intermediate, thus highlighting the role of Ag as a catalytic promoter for the oxidatively induced reactivity of the Rh catalyst in C3-substituted indoline synthesis.
铑(III)催化含有嘧啶导向基团的苯胺衍生物与乙烯基硅烷反应，生成 C3-取代的吲哚啉衍生物。通过密度泛函理论计算分析了反应路径和吲哚啉产物的形成。该研究表明，整个催化过程可以用以下阶段来描述：(I) 通过协同金属化脱质子的 C-H 活化，(II) 2,1-乙烯基硅烷插入，(III) NH 酰胺质子的去质子化，(IV) Ag 的氧化，以及(V) 还原消除。这些步骤在温和条件下从动力学和热力学上都是可行的，并且能进行实验实现，其势垒为 22.0 kcal/mol 的插入步骤不仅应该是区域选择性的关键步骤，而且应该是整个催化过程中的速率决定步骤。计算表明，Ag 的氧化可以在形成自然中间物后加速还原消除步骤，从而突出了 Ag 在 C3-取代的吲哚啉合成中 Rh 催化剂的氧化诱导反应性中的催化促进作用。
