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Structure and reactivity of germylene-bridged digold complexes.

ABSTRACT: The bonding between gold and main-group metallic elements (M) featuring Au^δ--M^δ+ polarity, has been studied recently. The gold in the bonds is expected to have the oxidation number of -1, and hence, nucleophilic. However, the knowledge of the reactivity of the gold-metal bonds remains limited. Here, we report digold-substituted germanes of the form of R'₂Ge(AuPR₃)(AuGeR'₂) (3a; R = Me, 3b; R = Et), featuring two Au-Ge(IV) and one Au-Ge(II) bonds. DFT calculations of 3a revealed the existence of high-lying σ(Ge-Au) type HOMO and low-lying LUMO with germylene p_π nature. A pendular motion of AuPR₃ group between Ge(IV) and Ge(II) of 3 occurs in the NMR time scale, suggesting that the Ge(II) center has an enhanced electrophilicity to be attacked by the nucleophilic gold (-I) atom. 3a reacts with nucleophilic Cl^- and electrophilic MeOTf reagents at Ge(II) and Ge(IV) centers, respectively.

SUBMITTER: Wang L

PROVIDER: S-EPMC8979951 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Structure and reactivity of germylene-bridged digold complexes.

Wang Liliang L Zhen Guorong G Li Yinhuan Y Kira Mitsuo M Yan Liping L Chang Xiao-Yong XY Huang Lu L Li Zhifang Z

Nature communications 20220404 1

The bonding between gold and main-group metallic elements (M) featuring Auδ--Mδ+ polarity, has been studied recently. The gold in the bonds is expected to have the oxidation number of -1, and hence, nucleophilic. However, the knowledge of the reactivity of the gold-metal bonds remains limited. Here, we report digold-substituted germanes of the form of R'2Ge(AuPR3)(AuGeR'2) (3a; R = Me, 3b; R = Et), featuring two Au-Ge(IV) and one Au-Ge(II) b ...[more]

PMID: 35379820

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