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Synthesis and Characterization of Hypercoordinated Silicon Anions: Catching Intermediates of Lewis Base Catalysis.

ABSTRACT: Anionic hypercoordinated silicates with weak donors were proposed as key intermediates in numerous silicon-based reactions. However, their short-lived nature rendered even spectroscopic observations highly challenging. Here, we characterize hypercoordinated silicon anions, including the first bromido-, iodido-, formato-, acetato-, triflato- and sulfato-silicates. This is enabled by a new, donor-free polymeric form of Lewis superacidic bis(perchlorocatecholato)silane 1. Spectroscopic, structural, and computational insights allow a reassessment of Gutmann's empirical rules for the role of silicon hypercoordination in synthesis and catalysis. The electronic perturbations of 1 exerted on the bound anions indicate pronounced substrate activation.

SUBMITTER: Ansmann N

PROVIDER: S-EPMC9325378 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Synthesis and Characterization of Hypercoordinated Silicon Anions: Catching Intermediates of Lewis Base Catalysis.

Ansmann Nils N Hartmann Deborah D Sailer Sonja S Erdmann Philipp P Maskey Rezisha R Schorpp Marcel M Greb Lutz L

Angewandte Chemie (International ed. in English) 20220505 27

Anionic hypercoordinated silicates with weak donors were proposed as key intermediates in numerous silicon-based reactions. However, their short-lived nature rendered even spectroscopic observations highly challenging. Here, we characterize hypercoordinated silicon anions, including the first bromido-, iodido-, formato-, acetato-, triflato- and sulfato-silicates. This is enabled by a new, donor-free polymeric form of Lewis superacidic bis(perchlorocatecholato)silane 1. Spectroscopic, structural, ...[more]

PMID: 35438836

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