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Dinuclear Au(I), Au(II) and Au(III) Complexes with (CF₂ )_n Chains: Insights into The Role of Aurophilic Interactions in the Au(I) Oxidation.

ABSTRACT: New dinuclear Au(I), Au(II) and Au(III) complexes containing (CF₂ )_n bridging chains were obtained. Metallomacrocycles [Au₂ {μ-(CF₂ )₄ }{μ-diphosphine}] show an uncommon figure-eight structure, the helicity inversion barrier of which is influenced by aurophilic interactions and steric constraints imposed by the diphosphine. Halogenation of LAu(CF₂ )₄ AuL (L=PPh₃ , PMe₃ , (dppf)_1/2 , (binap)_1/2 ) gave [Au(II)]₂ species, some of which display unprecedented folded structures with Au-Au bonds. Aurophilic interactions facilitate this oxidation process by preorganizing the starting [Au(I)]₂ complexes and lowering its redox potential. The obtained [Au(II)]₂ complexes undergo thermal or photochemical elimination of R₃ PAuX to give Au(III) perfluorinated auracycles. Evidence of a radical mechanism for these decomposition reactions was obtained.

SUBMITTER: Portugues A

PROVIDER: S-EPMC9291513 | biostudies-literature |

REPOSITORIES: biostudies-literature

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