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Activation of CS₂ and CO₂ by Silylium Cations.

ABSTRACT: The hydride-bridged silylium cation [Et₃ Si-H-SiEt₃ ]⁺ , stabilized by the weakly coordinating [Me₃ NB₁₂ Cl₁₁ ]^- anion, undergoes, in the presence of excess silane, a series of unexpected consecutive reactions with the valence-isoelectronic molecules CS₂ and CO₂ . The final products of the reaction with CS₂ are methane and the previously unknown [(Et₃ Si)₃ S]⁺ cation. To gain insight into the entire reaction cascade, numerous experiments with varying conditions were performed, intermediate products were intercepted, and their structures were determined by X-ray crystallography. Besides the [(Et₃ Si)₃ S]⁺ cation as the final product, crystal structures of [(Et₃ Si)₂ SMe]⁺ , [Et₃ SiS(H)Me]⁺ , and [Et₃ SiOC(H)OSiEt₃ ]⁺ were obtained. Experimental results combined with supporting quantum-chemical calculations in the gas phase and solution allow a detailed understanding of the reaction cascade.

SUBMITTER: Jenne C

PROVIDER: S-EPMC7898686 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Activation of CS2 and CO2 by Silylium Cations.

Jenne Carsten C Nierstenhöfer Marc C MC van Lessen Valentin V

Chemistry (Weinheim an der Bergstrasse, Germany) 20210112 10

The hydride-bridged silylium cation [Et3 Si-H-SiEt3 ]+ , stabilized by the weakly coordinating [Me3 NB12 Cl11 ]- anion, undergoes, in the presence of excess silane, a series of unexpected consecutive reactions with the valence-isoelectronic molecules CS2 and CO2 . The final products of the reaction with CS2 are methane and the previously unknown [(Et3 Si)3 S]+< ...[more]

PMID: 33215771

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