Understanding the Nature and Properties of Hydrogen–Hydrogen Bonds: The Stability of a Bulky Phosphatetrahedrane as a Case Study
Understanding the Nature and Properties of Hydrogen–Hydrogen Bonds: The Stability of a Bulky Phosphatetrahedrane as a Case Study
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了解氢-氢键的本质和性质：以大体积磷酸四面体的稳定性为例
DOI：
10.1021/acs.jpca.1c04046
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Cummins, Christopher C.
中科院分区：
文献类型：
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作者：
Riu, Martin-Louis Y.;Bistoni, Giovanni;Cummins, Christopher C.
最近，首次报道了混合C/P磷酸四面体(tBuC)3P和(tBuCP)2。与 (tBuCP)2 不同，(tBuC)3P 表现出显着的热稳定性，这部分归因于叔丁基取代基之间的九个氢-氢键 (HHB) 网络。该 HHB 网络产生的稳定贡献是通过在基于域的局部对自然轨道 CCSD(T) (DLPNO-CCSD(T)) 理论水平上计算的局部能量分解 (LED) 分析获得的。这些计算表明，每个 HHB 贡献大约 -0.7 kcal/mol 的稳定性；然而，由于空间排斥，净稳定能可能介于 -0.25 和 -0.5 kcal/mol 之间。通过色散相互作用密度 (DID) 图对伦敦色散能量进行空间分析表明，DID 表面位于 HHB 涉及的关键 C-H 基团处，这与主要由 HHB 产生的伦敦色散相互作用一致。此外，我们提出了一种计算机制，支持膦类化合物作为 (tBuC)3P 合成中的关键反应中间体。
Recently, the first mixed C/P phosphatetrahedranes (tBuC)3P and (tBuCP)2were reported. Unlike (tBuCP)2, (tBuC)3P exhibits remarkable thermal stability, which can be partially attributed to a network of nine hydrogen–hydrogen bonds (HHBs) localized between thetert-butyl substituents. The stabilizing contribution arising from this network of HHBs was obtained from local energy decomposition (LED) analysis calculated at the domain-based local pair natural orbital CCSD(T) (DLPNO-CCSD(T)) level of theory. These calculations suggest that each HHB contributes approximately −0.7 kcal/mol of stabilization; however, the net stabilization energy likely lies between −0.25 and −0.5 kcal/mol because of steric repulsion. Spatial analysis of the London dispersion energy via a dispersion interaction density (DID) plot reveals that the DID surface is localized at key C–H groups involved in HHBs, consistent with London dispersion interactions predominantly arising from HHBs. In addition, we present a computed mechanism that supports a phosphinidenoid species as a key reaction intermediate in the synthesis of (tBuC)3P.