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Chalcogen-Expanded Unsaturated Silicon Clusters: Thia-, Selena-, and Tellurasiliconoids.

ABSTRACT: Reactions of silylenes with heavier chalcogens (E) typically result in Si=E double bonds or their ?-addition products. In contrast, the oxidation of a silylene-functionalized unsaturated silicon cluster (siliconoid) with Group 16 elements selectively yields cluster expanded siliconoids Si₇ E (E=S, Se, Te) fully preserving the unsaturated nature of the cluster scaffold as evident from the NMR signatures of the products. Mechanistic considerations by DFT calculations suggest the intermediacy of a Si₆ siliconoid with exohedral Si=E functionality. The reaction thus may serve as model system for the oxidation of surface-bonded silylenes at Si(100) by chalcogens and their diffusion into the silicon bulk.

SUBMITTER: Poitiers NE

PROVIDER: S-EPMC7756652 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Chalcogen-Expanded Unsaturated Silicon Clusters: Thia-, Selena-, and Tellurasiliconoids.

Poitiers Nadine E NE Huch Volker V Zimmer Michael M Scheschkewitz David D

Chemistry (Weinheim an der Bergstrasse, Germany) 20201012 70

Reactions of silylenes with heavier chalcogens (E) typically result in Si=E double bonds or their π-addition products. In contrast, the oxidation of a silylene-functionalized unsaturated silicon cluster (siliconoid) with Group 16 elements selectively yields cluster expanded siliconoids Si<sub>7</sub> E (E=S, Se, Te) fully preserving the unsaturated nature of the cluster scaffold as evident from the NMR signatures of the products. Mechanistic considerations by DFT calculations suggest the interme ...[more]

PMID: 32700779

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