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Low-Coordinate Iron Hydride Chemistry at an N,N,C-Heteroscorpionate Platform.

ABSTRACT: Locally high-spin iron hydrides are proposed to play a critical role as intermediates in iron-molybdenum cofactor (FeMoco)-catalyzed N₂ fixation. Inspired by these biological systems, we report herein our initial investigations into low-coordinate iron hydride chemistry supported by our N,N,C-heteroscorpionate ligands. Those ligands with smaller steric profiles are unable to completely suppress the formation of a binuclear [Fe(μ₂-H)]₂ complex; however, the incorporation of more substantial steric bulk allows for the isolation of a rare example of a terminal, high-spin (S = 2) Fe²⁺ hydride. Fourier transform infrared spectroscopy suggests an unusually weak Fe-H bond in the latter molecule. Mössbauer spectroscopies, coupled with density functional theory calculations, highlights the substantial influence of the terminal hydride ligand on ⁵⁷Fe isomer shift.

SUBMITTER: Fraker A

PROVIDER: S-EPMC11304392 | biostudies-literature | 2024 Aug

REPOSITORIES: biostudies-literature

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Low-Coordinate Iron Hydride Chemistry at an N,N,C-Heteroscorpionate Platform.

Fraker Addison A Linn Brittany N BN McSkimming Alex A

Inorganic chemistry 20240722 31

Locally high-spin iron hydrides are proposed to play a critical role as intermediates in iron-molybdenum cofactor (FeMoco)-catalyzed N2 fixation. Inspired by these biological systems, we report herein our initial investigations into low-coordinate iron hydride chemistry supported by our N,N,C-heteroscorpionate ligands. Those ligands with smaller steric profiles are unable to completely suppress the formation of a binuclear [Fe(μ2-H)]2 complex; however, the incorp ...[more]

PMID: 39037731

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