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NHCs as Neutral Donors towards Polyphosphorus Complexes.

ABSTRACT: The first adducts of NHCs (=N-heterocyclic carbenes) with aromatic polyphosphorus complexes are reported. The reactions of [Cp*Fe(?⁵ -P₅ )] (1) (Cp*=pentamethyl-cyclopentadienyl) with IMe (=1,3,4,5-tetramethylimidazolin-2-ylidene), IMes (=1,3-bis(2,4,6-trimethylphenyl)-imidazolin-2-ylidene) and IDipp (=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene) led to the corresponding neutral adducts which can be isolated in the solid state. However, in solution, they quickly undergo a dissociative equilibrium between the adduct and 1 including the corresponding NHC. The equilibrium is influenced by the bulkiness of the NHC. [Cp''Ta(CO)₂ (?⁴ -P₄ )] (Cp''=1,3-di-tert-butylcyclopentadienyl) reacts with IMe under P atom abstraction to give an unprecedented cyclo-P₃ -containing anionic tantalum complex. DFT calculations shed light onto the energetics of the reaction pathways.

SUBMITTER: Riedlberger F

PROVIDER: S-EPMC7756228 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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NHCs as Neutral Donors towards Polyphosphorus Complexes.

Riedlberger Felix F Todisco Stefano S Mastrorilli Piero P Timoshkin Alexey Y AY Seidl Michael M Scheer Manfred M

Chemistry (Weinheim an der Bergstrasse, Germany) 20201029 69

The first adducts of NHCs (=N-heterocyclic carbenes) with aromatic polyphosphorus complexes are reported. The reactions of [Cp*Fe(η<sup>5</sup> -P<sub>5</sub> )] (1) (Cp*=pentamethyl-cyclopentadienyl) with IMe (=1,3,4,5-tetramethylimidazolin-2-ylidene), IMes (=1,3-bis(2,4,6-trimethylphenyl)-imidazolin-2-ylidene) and IDipp (=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene) led to the corresponding neutral adducts which can be isolated in the solid state. However, in solution, they quickly und ...[more]

PMID: 32745336

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