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Aryl-Aryl Interactions in (Aryl-Perhalogenated) 1,2-Diaryldisilanes.

ABSTRACT: Three 1,2-diaryltetramethyldisilanes X₅ C₆ -(SiMe₂ )₂ -C₆ X₅ with two C₆ H₅ , C₆ F₅ , or C₆ Cl₅ groups were studied concerning the importance of London dispersion driven interactions between their aryl groups. They were prepared from 1,2-dichlorotetramethyldisilane by salt elimination. Their structures were determined in the solid state by X-ray diffraction and for free molecules by gas electron-diffraction. The solid-state structures of the fluorinated and chlorinated derivatives are dominated by aryl-aryl interactions. Unexpectedly, Cl₅ C₆ -(SiMe₂ )₂ -C₆ Cl₅ exists exclusively as an eclipsed syn-conformer in the gas phase with strongly distorted Si-C₆ Cl₅ units due to strong intramolecular interactions. In contrast, F₅ C₆ -(SiMe₂ )₂ -C₆ F₅ reveals weaker interactions. The contributions to the total interaction energy were analyzed by SAPT calculations.

SUBMITTER: Linnemannstons M

PROVIDER: S-EPMC7065172 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Aryl-Aryl Interactions in (Aryl-Perhalogenated) 1,2-Diaryldisilanes.

Linnemannstöns Marvin M Schwabedissen Jan J Neumann Beate B Stammler Hans-Georg HG Berger Raphael J F RJF Mitzel Norbert W NW

Chemistry (Weinheim an der Bergstrasse, Germany) 20200130 10

Three 1,2-diaryltetramethyldisilanes X5 C6 -(SiMe2 )2 -C6 X5 with two C6 H5 , C6 F5 , or C6 Cl5 groups were studied concerning the importance of London dispersion driven interactions between their aryl groups. They were prepared from 1,2-dichlorotetramethyldisilane by salt elimination. Their structures were determined in the solid state by X-ray diffraction and for ...[more]

PMID: 31859375

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