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On the σ-complex character of bis(gallyl)/digallane transition metal species.

ABSTRACT: σ-complexes of homoatomic E-E bonds are key intermediates in catalytically relevant oxidative addition reactions, but are as yet unknown for the group 13 elements. Here, stable species best described as σ-complexes of a 1,2-dichlorodigallane derivative with Ni and Pd are reported. They are readily accessed through the combination of a 1,2-dichlorodigallane derivative, which features chelating phosphine functionalities, with Ni⁰ and Pd⁰ synthons. In-depth computational analyses of these complexes importantly reveal considerable Ga-Ga bonding interactions in both Ni and Pd complexes, despite the expected elongation of the Ga-Ga bond upon complexation, suggestive of σ-complex character as opposed to more commonly described bis(gallyl) character. Finally, the well-defined disproportion of the Ni complex is described, leading to a unique Ga^I-nickel complex, with concomitant expulsion of uncomplexed Ga^III species.

SUBMITTER: Kalkuhl TL

PROVIDER: S-EPMC10583741 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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On the σ-complex character of bis(gallyl)/digallane transition metal species.

Kalkuhl Till L TL Qin Lei L Zhao Lili L Frenking Gernot G Hadlington Terrance J TJ

Chemical science 20230922 40

σ-complexes of homoatomic E-E bonds are key intermediates in catalytically relevant oxidative addition reactions, but are as yet unknown for the group 13 elements. Here, stable species best described as σ-complexes of a 1,2-dichlorodigallane derivative with Ni and Pd are reported. They are readily accessed through the combination of a 1,2-dichlorodigallane derivative, which features chelating phosphine functionalities, with Ni<sup>0</sup> and Pd<sup>0</sup> synthons. In-depth computational analy ...[more]

PMID: 37860650

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