1. Hexaphenylditetrels – When Longer Bonds Provide Higher Stability
- Author
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Peter R. Schreiner, Lars Rummel, and Jan M. Schümann
- Subjects
bond strength ,Bond strength ,Communication ,bond dissociation energy ,Organic Chemistry ,General Chemistry ,Stability (probability) ,London dispersion force ,Bond-dissociation energy ,Catalysis ,Dissociation (chemistry) ,Communications ,chemistry.chemical_compound ,C−H-π-interactions ,chemistry ,Pauli repulsion ,Chemical physics ,Hexaphenylethane ,Very Important Paper ,Chemical stability ,London dispersion ,Perturbation theory - Abstract
We present a computational analysis of hexaphenylethane derivatives with heavier tetrels comprising the central bond. In stark contrast to parent hexaphenylethane, the heavier tetrel derivatives can readily be prepared. In order to determine the origin of their apparent thermodynamic stability against dissociation as compared to the carbon case, we employed local energy decomposition analysis (LED) and symmetry‐adapted perturbation theory (SAPT) at the DLPNO‐CCSD(T)/def2‐TZVP and sSAPT0/def2‐TZVP levels of theory. We identified London dispersion (LD) interactions as the decisive factor for the molecular stability of heavier tetrel derivatives. This stability is made possible owing to the longer (than C−C) central bonds that move the phenyl groups out of the heavily repulsive regime so they can optimally benefit from LD interactions., Carbon‐Carbon bonds are exceptional as demonstrated for the hexaphenylditetrels where attractive London dispersion interactions are the decisive factor for the thermodynamic stabilities of tetrels other than carbon. Structural and energetic comparisons show that even though hexaphenylethane displays the largest dispersion energy between the two molecular halves, it has remained elusive because of even larger Pauli repulsion of the phenyl moieties that are forced in close contact due to the C−C bond that is the shortest in this series.
- Published
- 2021