Effect of the [Fe(salen)]2-μ-oxo Catalyst Electronic Structure on Reductive Hydroamination

Emily Pocock; Nathan J. Buxton; Martin Diefenbach; Andrew D. Bond; Simon E. Lewis; Vera Krewald; Ruth L. Webster

doi:10.1021/acs.inorgchem.5c05628

Effect of the [Fe(salen)]₂-μ-oxo Catalyst Electronic Structure on Reductive Hydroamination

Emily Pocock, Nathan J. Buxton, Martin Diefenbach, Andrew D. Bond, Simon E. Lewis, Vera Krewald, Ruth L. Webster

Research output: Contribution to journal › Article › peer-review

Abstract

Salen ligands are privileged scaffolds in transition metal catalysis due to their electronic tunability and capacity to stabilize diverse oxidation states. Herein, we report the synthesis and comparative study of three electronically differentiated [Fe(salen)]₂(μ-oxo) complexes and their application in catalytic reductive hydroamination (HA) of nitroarenes with alkenes. A mechanistic framework involving iron-hydride intermediates and hydrogen atom transfer (HAT) was developed, revealing that modulation of the salen ligand electronics significantly impacts product distribution and catalytic efficiency. Systematic investigation of substrate LUMO energies and precatalyst UV–vis spectroscopy, cyclic voltammetry, along with DFT calculations on the key HAT step, was undertaken. Notably, the complex bearing para-CF₃ substituents outperformed its analogues across a range of olefin partners. These findings underscore the critical role of ligand electronics in tuning HAT-based catalysis.

Original language	English
Pages (from-to)	999-1007
Number of pages	9
Journal	Inorganic Chemistry
Volume	65
Issue number	1
Early online date	20 Dec 2025
DOIs	https://doi.org/10.1021/acs.inorgchem.5c05628
Publication status	Published - 12 Jan 2026

Funding

This research was supported through an iCASE PhD studentship (AstraZeneca/EPSRC awarded to E.P.), a Leverhulme Trust Research Project Grant (RPG-2020-313, awarded to M.D., V.K., R.L.W.), the Philip Leverhulme Prize (R.L.W., N.J.B.) and research funds awarded to R.L.W. from the Yusuf Hamied Department of Chemistry, University of Cambridge. Funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) through grant 510228793/SFB 1633 (TP A02) is gratefully acknowledged. Calculations for this research were conducted on the Lichtenberg high-performance computer of the TU Darmstadt.

ASJC Scopus subject areas

Physical and Theoretical Chemistry
Inorganic Chemistry

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Cite this

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AU - Pocock, Emily

AU - Buxton, Nathan J.

AU - Diefenbach, Martin

AU - Bond, Andrew D.

AU - Lewis, Simon E.

AU - Krewald, Vera

AU - Webster, Ruth L.

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