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Low-Valent Germanylidene Anions: Efficient Single-Site Nucleophiles for Activation of Small Molecules.

ABSTRACT: Rare mononuclear and helical chain low-valent germanylidene anions supported by cyclic (alkyl)(amino)carbene and hypermetallyl ligands were synthesised by stepwise reduction from corresponding germylene precursors via stable and isolable germanium radicals. The electronic structures of the anions can be described with ylidene and ylidone resonance forms with the Ge-C π-electrons capable of binding even weak electrophiles. The germanylidene anions reacted with CO₂ to give μ-CO₂ -κC:κO complexes, a rare coordination mode for low-valent germanium and inaccessible for the related neutral germylones. These results implicate low-valent germanylidene anions as efficient single-site nucleophiles for activation of small molecules.

SUBMITTER: Gendy C

PROVIDER: S-EPMC8596740 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Low-Valent Germanylidene Anions: Efficient Single-Site Nucleophiles for Activation of Small Molecules.

Gendy Chris C Mikko Rautiainen J J Mailman Aaron A Tuononen Heikki M HM

Chemistry (Weinheim an der Bergstrasse, Germany) 20210915 58

Rare mononuclear and helical chain low-valent germanylidene anions supported by cyclic (alkyl)(amino)carbene and hypermetallyl ligands were synthesised by stepwise reduction from corresponding germylene precursors via stable and isolable germanium radicals. The electronic structures of the anions can be described with ylidene and ylidone resonance forms with the Ge-C π-electrons capable of binding even weak electrophiles. The germanylidene anions reacted with CO<sub>2</sub> to give μ-CO<sub>2</s ...[more]

PMID: 34403540

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