Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong, People's Republic of China.
Inorg Chem. 2013 Sep 16;52(18):10449-55. doi: 10.1021/ic401289k. Epub 2013 Sep 6.
η(5)-η(1) ring slippage of [OsCp2] (Cp = η(5)-C5H5) and [Ru(η(5)-ind)2] (ind = indenyl) resulting from reaction with the ruthenium(VI) nitride [Ru(L(OEt))(N)Cl2] (1; L(OEt)(-) = CoCp{P(O)(OEt)2}3) is reported. The treatment of [OsCp2] or [Ru(η(5)-ind)2] with 1 resulted in η(5)-η(1) ring slippage of the cycloolefin ligands and formation of the trinuclear nitrido complexes [Cp(η(1)-C5H5)Os(NRuL(OEt)Cl2)2] (2) or [(η(5)-ind)(η(1)-ind)Ru(NRuL(OEt)Cl2)2] (3). No reactions were found between [OsCp2] and amines, such as pyridine and 2,2'-bipyridyl, or other metal nitrides, such as [Os(L(OEt))(N)Cl2], indicating that the electrophilic property of 1 is essential for ring slippage. The crystal structures of 2 and 3 have been determined. The short Os-N distances in 2 [1.833(5) and 1.817(5) Å] and the (ind)Ru-N distances in 3 [1.827(5) and 1.852(5) Å] are indicative of multiple bond character, consistent with density functional theory (DFT) calculations. Therefore, 2 and 3 may be described by two resonance forms: Ru(VI)-M(II)-Ru(VI) and Ru(IV)-M(VI)-Ru(IV) (M = Os, Ru). Also, DFT calculations indicate that for the reaction of 1 with [OsCp2] or [Ru(η(5)-ind)2], η(5)-η(1) ring slippage is energetically more favorable than the η(5)-η(3) counterpart. The driving force for η(5)-η(1) ring slippage is believed to be the formation of the strong M-N (M = Os, Ru) (multiple) bonds. By contrast, the same reaction with acetonitrile is energetically uphill, and thus no ring slippage occurs.
[OsCp2]（Cp = η(5)-C5H5）和[Ru(η(5)-ind)2]（ind = 茚基）与六价氮化物[Ru(L(OEt))(N)Cl2]（1；L(OEt)(-) = CoCp{P(O)(OEt)2}3)反应导致[η(5)-η(1)环滑动]。用 1 处理[OsCp2]或[Ru(η(5)-ind)2]导致环烯烃配体的η(5)-η(1)环滑动，并形成三核氮化物配合物[Cp(η(1)-C5H5)Os(NRuL(OEt)Cl2)2]（2）或[(η(5)-ind)(η(1)-ind)Ru(NRuL(OEt)Cl2)2]（3）。在[OsCp2]和胺（如吡啶和 2,2'-联吡啶）或其他金属氮化物（如[Os(L(OEt))(N)Cl2]）之间未发现反应，表明 1 的亲电性对于环滑动是必不可少的。2 和 3 的晶体结构已经确定。2 中短的 Os-N 距离[1.833(5)和 1.817(5) Å]和 3 中（ind）Ru-N 距离[1.827(5)和 1.852(5) Å]表明存在多重键性质，与密度泛函理论（DFT）计算一致。因此，2 和 3 可以用两种共振形式描述：Ru(VI)-M(II)-Ru(VI)和 Ru(IV)-M(VI)-Ru(IV)（M = Os，Ru）。此外，DFT 计算表明，对于 1 与[OsCp2]或[Ru(η(5)-ind)2]的反应，η(5)-η(1)环滑动在能量上比η(5)-η(3)对应物更有利。η(5)-η(1)环滑动的驱动力被认为是形成强 M-N（M = Os，Ru）（多重）键。相比之下，与乙腈的相同反应在能量上是上坡的，因此不会发生环滑动。
