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High-Spin Imido Cobalt Complexes with Imidyl Radical Character*.

ABSTRACT: We report on the synthesis of a variety of trigonal imido cobalt complexes [Co(NAryl)L₂ ]^- , (L=N(Dipp)SiMe₃ ), Dipp=2,6-diisopropylphenyl) with very long Co-N_Aryl bonds of around 1.75 Å. Their electronic structure was interrogated using a variety of physical and spectroscopic methods such as EPR or X-Ray absorption spectroscopy which leads to their description as highly unusual imidyl cobalt complexes. Computational analyses corroborate these findings and further reveal that the high-spin state is responsible for the imidyl character. Exchange of the Dipp substituent on the imide by the smaller mesityl function (2,4,6-trimethylphenyl) effectuates the unexpected Me₃ Si shift from the ancillary ligand set to the imidyl nitrogen, revealing a highly reactive, nucleophilic character of the imidyl unit.

SUBMITTER: Reckziegel A

PROVIDER: S-EPMC8362137 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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High-Spin Imido Cobalt Complexes with Imidyl Radical Character*.

Reckziegel Alexander A Kour Manjinder M Battistella Beatrice B Mebs Stefan S Beuthert Katrin K Berger Robert R Werncke C Gunnar CG

Angewandte Chemie (International ed. in English) 20210609 28

We report on the synthesis of a variety of trigonal imido cobalt complexes [Co(NAryl)L2 ]- , (L=N(Dipp)SiMe3 ), Dipp=2,6-diisopropylphenyl) with very long Co-NAryl bonds of around 1.75 Å. Their electronic structure was interrogated using a variety of physical and spectroscopic methods such as EPR or X-Ray absorption spectroscopy which leads to their description as highly unusual imidyl cobalt complexes. Computational analyses corroborate these findings ...[more]

PMID: 33977634

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