A novel N‐hetero‐Rh^I‐metallacyclic silanone 2 has been synthesized. The silanone 2, showing an extremely large dimerization energy (ΔG=+86.2 kcal mol⁻¹), displays considerable stability and persists in solution up to 60 °C. Above 120 °C, an intramolecular C_sp3−H insertion occurs slowly over a period of two weeks leading to the bicyclic silanol 5. The exceptional stability of 2, related to the unusual electronic and steric effects of Rh^I‐substituent, should allow for a more profound study and understanding of these new species. Furthermore, the metallacyclic silanone 2 presents two reactive centers (Si=O and Rh), which can be involved depending upon the nature of reagents. Of particular interest, the reaction with H₂ starts with the hydrogenation of Rh^I center leading to the corresponding Rh^III‐dihydride complex 7 and it undergoes a cis/trans‐isomerization via a particular mechanism, demonstrating that addition‐elimination processes can also happen for silanones just like for their carbon analogues!

中文翻译：

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稳定的N-杂-RhI-金属环硅酮的合成。

合成了一种新颖的N-Rh ^I-金属杂环硅酮2。显示出非常大的二聚能（ΔG = + 86.2 kcal mol ^-1）的硅酮2显示出相当大的稳定性，并且在高达60°C的溶液中仍然存在。在120℃以上，分子内C _sp3- H插入在两周内缓慢发生，从而导致双环硅烷醇5。的优异的稳定性2，与铑的不寻常的电子和空间效应^我-取代，应该允许这些新物种的更深刻的研究和理解。此外，金属环硅酮2存在两个反应中心（Si = O和Rh），具体取决于试剂的性质。特别令人感兴趣的是，与H ₂的反应始于Rh ^I中心的氢化反应，生成相应的Rh ^III-二氢化物络合物7，并且它通过一种特殊的机理经历了顺式/反式异构化，这表明加成消除过程也可能发生就像它们的碳类似物一样