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Tuning ligand field strength with pendent Lewis acids: access to high spin iron hydrides.

ABSTRACT: Geometrically flexible 9-borabicyclo[3.3.1]nonyl units within the secondary coordination sphere enable isolation of high-spin Fe(ii)-dihydrides stabilized by boron-hydride interactions and a rare example of an isolable S = 3/2 reduction product. The borane-capped Fe(ii)-dihydride: (1) rapidly deprotonates E-H (E = N, O, P, S) bonds to afford borane-stabilized Fe adducts and (2) releases H₂ upon exposure to ?-acids. The Lewis acids provide an avenue for redox-leveling in analogy to the near constant operating potential for N₂ reduction in nitrogenase.

SUBMITTER: Kiernicki JJ

PROVIDER: S-EPMC6553361 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Tuning ligand field strength with pendent Lewis acids: access to high spin iron hydrides.

Kiernicki John J JJ Shanahan James P JP Zeller Matthias M Szymczak Nathaniel K NK

Chemical science 20190507 21

Geometrically flexible 9-borabicyclo[3.3.1]nonyl units within the secondary coordination sphere enable isolation of high-spin Fe(ii)-dihydrides stabilized by boron-hydride interactions and a rare example of an isolable S = 3/2 reduction product. The borane-capped Fe(ii)-dihydride: (1) rapidly deprotonates E-H (E = N, O, P, S) bonds to afford borane-stabilized Fe adducts and (2) releases H2 upon exposure to π-acids. The Lewis acids provide an avenue for redox-leveling in analogy ...[more]

PMID: 31293738

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