Experimental and theoretical studies of the rhodium(i)-catalysed C-H oxidative alkenylation/cyclization of N-(2-(methylthio)phenyl)benzamides with maleimides
Experimental and theoretical studies of the rhodium(i)-catalysed C-H oxidative alkenylation/cyclization of N-(2-(methylthio)phenyl)benzamides with maleimides
复制标题
DOI：
10.1039/d3qo00023k
复制
发表时间：
2023-02-13
影响因子：
5.4
通讯作者：
Chatani，Naoto
中科院分区：
文献类型：
--
作者：
Skhiri，Aymen;Taborosi，Attila;Chatani，Naoto
铑（I）催化的含有2-（甲硫基）苯胺导向基团的芳族酰胺与马来酰亚胺的反应在有氧、无金属氧化物和无溶剂条件下得到作为产物的异吲哚酮螺琥珀酰亚胺。与我们先前关于芳香酰胺的C-H烷基化的研究（其中使用8-氨基喹啉导向基团）形成鲜明对比，使用（2-甲硫基）苯胺导向基团导致C-H氧化烯基化/环化。马来酰亚胺具有双重功能，即，既作为偶联配偶体又作为氢受体。通过密度泛函理论（DFT）计算研究了几种可能的反应路径，以澄清负责形成异吲哚酮螺琥珀酰亚胺产品的机制。深入计算研究的结果表明，反应通过以下主要步骤进行：（I）邻位C-H键的氧化加成和马来酰亚胺的迁移插入，（II）将第二分子马来酰亚胺插入到罗达霉素中的Rh-C键中，形成C-C键，随后进行配体-配体氢转移（LLHT），（III）酰胺和马来酰亚胺之间的C-N键形成，和（IV）PivOH质子化。使用一个充满活力的跨度模型沿着与动力学同位素效应的测定表明，决定过渡态的反应步骤是氧化加成/迁移插入步骤。
The rhodium(I)-catalysed reaction of aromatic amides that contain a 2-(methylthio)aniline directing group with maleimides gives isoindolone spirosuccinimides as products under aerobic, metal oxidant-free, and solvent-free conditions. In sharp contrast to our previous study on the C–H alkylation of aromatic amides in which an 8-aminoquinoline directing group was used, the use of a (2-methylthio)aniline directing group resulted in C–H oxidative alkenylation/cyclization. The maleimide has dual functions, i.e., serving as both a coupling partner and a hydrogen acceptor. Several possible reaction paths were examined by density functional theory (DFT) calculations to clarify the mechanism responsible for the formation of the isoindolone spirosuccinimide products. The results of an in-depth computational study indicate that the reaction proceeds via the following main steps: (I) oxidative addition of the ortho C–H bond and the migratory insertion of the maleimide, (II) the insertion of a second molecule of maleimide into a Rh–C bond in a rhodacycle with the formation of a C–C bond and subsequent ligand–ligand hydrogen transfer (LLHT), (III) C–N bond formation between the amide and the maleimide, and (IV) PivOH protonation. The use of an energetic span model along with the determination of the kinetic isotopic effect showed that the determining transition state step for the reaction is the oxidative addition/migratory insertion step.