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A Terminal Imido Complex of an Iron-Sulfur Cluster.

ABSTRACT: We report the synthesis and characterization of the first terminal imido complex of an Fe-S cluster, (IMes)₃ Fe₄ S₄ =NDipp (2; IMes=1,3-dimesitylimidazol-2-ylidene, Dipp=2,6-diisopropylphenyl), which is generated by oxidative group transfer from DippN₃ to the all-ferrous cluster (IMes)₃ Fe₄ S₄ (PPh₃ ). This two-electron process is achieved by formal one-electron oxidation of the imido-bound Fe site and one-electron oxidation of two IMes-bound Fe sites. Structural, spectroscopic, and computational studies establish that the Fe-imido site is best described as a high-spin Fe³⁺ center, which is manifested in its long Fe-N(imido) distance of 1.763(2) Å. Cluster 2 abstracts hydrogen atoms from 1,4-cyclohexadiene to yield the corresponding anilido complex, demonstrating competency for C-H activation.

SUBMITTER: Sridharan A

PROVIDER: S-EPMC8294340 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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A Terminal Imido Complex of an Iron-Sulfur Cluster.

Sridharan Arun A Brown Alexandra C AC Suess Daniel L M DLM

Angewandte Chemie (International ed. in English) 20210429 23

We report the synthesis and characterization of the first terminal imido complex of an Fe-S cluster, (IMes)3 Fe4 S4 =NDipp (2; IMes=1,3-dimesitylimidazol-2-ylidene, Dipp=2,6-diisopropylphenyl), which is generated by oxidative group transfer from DippN3 to the all-ferrous cluster (IMes)3 Fe4 S4 (PPh3 ). This two-electron process is achieved by formal one-electron oxidation of the imido-bound Fe site and one-el ...[more]

PMID: 33772994

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