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Diphosphorus Release and Heterocumulene Oligomerisation by Nickel Complexes.

ABSTRACT: The generation of diphosphorus molecules P₂ under mild conditions in solution is a useful strategy to generate diphosphines via [4+2] cycloadditions. We recently described the release of P₂ units from the nickel butterfly complex [{(IMes)Ni(CO)}₂(μ²,η²:η²-P₂)] (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) upon addition of CO gas. Herein, we developed an alternative protocol for the same process using heterocumulenes. In addition to formation of P₄ (the dimerisation product of P₂), the reactions afford nickel complexes of novel pincer-type ligands. Aryl isothiocyanates undergo a trimerisation within the coordination sphere of nickel and afford square planar nickel complexes with S-C-S pincer-ligand frameworks. Carbon disulfide coordinates to the [(IMes)Ni]-fragment in an η²-fashion, affording a dinuclear complex. Similar products are formed when the N-heterocyclic carbene nickel(0) complex [(IMes)Ni(vtms)₂] is used as a precursor (vtms=vinyltrimethylsilane).

SUBMITTER: Hierlmeier G

PROVIDER: S-EPMC9314841 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Diphosphorus Release and Heterocumulene Oligomerisation by Nickel Complexes.

Hierlmeier Gabriele G Wolf Robert R

European journal of inorganic chemistry 20220314 10

The generation of diphosphorus molecules P2 under mild conditions in solution is a useful strategy to generate diphosphines via [4+2] cycloadditions. We recently described the release of P2 units from the nickel butterfly complex [{(IMes)Ni(CO)}2(μ2,η2:η2-P2)] (IMes=1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) upon addition of CO gas. Herein, we developed an alternative protocol for the same process using ...[more]

PMID: 35915815

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