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Three-membered cyclic digermylenes stabilised by an N-heterocyclic carbene.

ABSTRACT: Treatment of potassium salts of silole dianions with donor stabilised germanium dichlorides gave the anticipated silagermafulvenylidenes R₂Si = Ge(Do) (R₂Si = 1-silacyclopentadiendiyl, Do = N-heterocyclic carbene (NHC)) only as transient intermediates in a side reaction. They were detected by NMR spectroscopy and, in one case, the formal dimer, 2,4-disila-1λ³,3λ³-digermetane, was isolated. The main products of these reactions are sila-bis-λ³-germiranes, i.e. directly interconnected digermylenes that are part of a three-membered ring. The structural data, supported by the results of density functional calculations confirm the digermylene nature of these products with a long inner cyclic Ge-Ge bond that decreases the inherent high ring strain in silagermiranes.

SUBMITTER: Dong Z

PROVIDER: S-EPMC8115106 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Three-membered cyclic digermylenes stabilised by an N-heterocyclic carbene.

Dong Zhaowen Z Winkler Jan Mathis JM Schmidtmann Marc M Müller Thomas T

Chemical science 20210322 18

Treatment of potassium salts of silole dianions with donor stabilised germanium dichlorides gave the anticipated silagermafulvenylidenes R2Si = Ge(Do) (R2Si = 1-silacyclopentadiendiyl, Do = N-heterocyclic carbene (NHC)) only as transient intermediates in a side reaction. They were detected by NMR spectroscopy and, in one case, the formal dimer, 2,4-disila-1λ3,3λ3-digermetane, was isolated. The main products of these reactions are sila-bis-λ3 ...[more]

PMID: 34084426

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