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A Zwitterionic Heterobimetallic Gold-Iron Complex Supported by Bis(N-Heterocyclic Imine)Silyliumylidene.

ABSTRACT: The facile synthesis of the first bis-N-heterocyclic imine-stabilized chlorosilyliumylidene 1 is reported. Remarkably, consecutive reaction of 1 with PPh₃ AuCl and K₂ Fe(CO)₄ gives rise to the unique heterobimetallic complex 1,2-(^Mes NHI)₂ -C₂ H₄ -ClSiAuFe(CO)₄ (4). The overall neutral complex 4 bears an unusual linear Si-Au-Fe structure and a rare anagostic interaction between the d¹⁰ -configured gold atom and a CH bond of the mesityl ligand. According to the computational analysis and ⁵⁷ Fe Mössbauer spectroscopy, the formal Fe-oxidation state remains at -II. Thus, the electronic structure of 4 is best described as an overall neutral-yet zwitterionic-heterobimetallic "Si(II)⁺ -Au(I)⁺ -Fe(-II)^2- "-silyliumylidene complex, derived from double anion exchange. The computational analysis indicates strong hyperconjugative back donation from the gold(I) atom to the silyliumylidene ligand.

SUBMITTER: Hanusch F

PROVIDER: S-EPMC8596601 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Heterobimetallic Coinage Metal-Ruthenium Complexes Supported by Anionic N-Heterocyclic Carbenes.

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