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Fischer Carbene Complexes of Iridium(I) for Application in Catalytic Transfer Hydrogenation.

ABSTRACT: New examples of the very rare class of iridium(I) Fischer carbene complexes (FCCs) are reported from the facile transmetalation from group 6 FCCs. Postcomplexation modification of either the carbene ligand or the ancillary coligands results in a tunable Ir^I metal center, for unprecedented application as a (pre)catalyst in a benchmark transfer hydrogenation reaction. The introduction of an aminocarbene ligand with a pendant N-donor moiety capable of hemilabile coordination yielded the best catalytic results with turnover frequencies reaching 445 h^-1 and requiring 0.1 mol % catalyst and 0.5 mol % base loading, respectively.

SUBMITTER: Ramollo GK

PROVIDER: S-EPMC7311058 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Fischer Carbene Complexes of Iridium(I) for Application in Catalytic Transfer Hydrogenation.

Ramollo G Kabelo GK Strydom Ian I Fernandes Manuel A MA Lemmerer Andreas A Ojwach Stephen O SO van Wyk Juanita L JL Bezuidenhout Daniela I DI

Inorganic chemistry 20200326 7

New examples of the very rare class of iridium(I) Fischer carbene complexes (FCCs) are reported from the facile transmetalation from group 6 FCCs. Postcomplexation modification of either the carbene ligand or the ancillary coligands results in a tunable Ir<sup>I</sup> metal center, for unprecedented application as a (pre)catalyst in a benchmark transfer hydrogenation reaction. The introduction of an aminocarbene ligand with a pendant N-donor moiety capable of hemilabile coordination yielded the ...[more]

PMID: 32212623

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