Room temperature photo-promoted iron-catalysed arene c–h alkenylation without grignard reagents

ABSTRACT Iron is inexpensive, non-toxic and the most abundant transition metal in the Earth’s crust, rendering iron-catalysed C–H activations attractive yet particularly challenging. Despite

major advances, iron-catalysed C–H activations have been linked to high reaction temperatures or the use of reactive Grignard reagents. Here we present iron-catalysed ketimine C–H

activations at ambient reaction temperature with the help of blue light in the absence of additives, utilizing easily accessible _cis_-[Fe(H)2(dppe)2] (where dppe is

1,2-bis(diphenylphosphino)ethane) as a single component precatalyst. Mild reaction conditions, high atom economy and the lack of Grignard reagents are distinguishing features of the

iron-catalysed C–H alkenylation manifold. Detailed mechanistic investigations by deuterium labelling, isolation of organometallic intermediates and in operando light-emitting diode nuclear

magnetic resonance spectroscopy revealed the role of the light and an oxidative addition to an iron(0) complex as the modus operandi for the C–H activation. Access through your institution

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C(_SP_²)–H ACTIVATION FOR AZA-ANNULATION WITH ALKYNES ON EXTENDED _Π_-CONJUGATED SYSTEMS Article 09 July 2024 PHOTOCHEMICAL DIAZIDATION OF ALKENES ENABLED BY LIGAND-TO-METAL CHARGE TRANSFER

AND RADICAL LIGAND TRANSFER Article Open access 23 December 2022 BIFUNCTIONAL IRON-CATALYZED ALKYNE _Z_-SELECTIVE HYDROALKYLATION AND TANDEM _Z_-_E_ INVERSION VIA RADICAL MOLDING AND

FLIPPING Article Open access 04 October 2024 DATA AVAILABILITY The data supporting the findings of this study are available within the article and its Supplementary Information, or from the

authors on reasonable request. Crystal structure data have been deposited at the Cambridge Crystallographic Data Centre (CCDC nos. 2192211–2192227 and 2280102–2280104), and crystallographic

data are provided in Supplementary Information. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk. Spectroscopic and kinetic

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_J. Am. Chem. Soc._ 121, 4369–4378 (1999). CAS  Google Scholar  Download references ACKNOWLEDGEMENTS Generous support by the DFG (SPP 1807 Gottfried-Wilhelm-Leibniz award to L.A.), the

European Union’s Horizon 2020 research and innovation programme (Marie Skłodowska-Curie grant agreement no. 895404 to A.M.M. and ERC advanced grant agreement no. 101021358 to L.A.) and FCI

Kekulé Fellowship no. 110091 (T.v.M.) is gratefully acknowledged. We thank C. Golz (Göttingen University) for assistance with the X-ray diffraction analysis and I. Maksso for measuring

inductively coupled plasma mass spectrometry solutions. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen,

Göttingen, Germany Antonis M. Messinis, Tristan von Münchow, Max Surke & Lutz Ackermann * Wöhler-Research Institute for Sustainable Chemistry, Georg-August-Universität Göttingen,

Göttingen, Germany Antonis M. Messinis, Tristan von Münchow & Lutz Ackermann Authors * Antonis M. Messinis View author publications You can also search for this author inPubMed Google

Scholar * Tristan von Münchow View author publications You can also search for this author inPubMed Google Scholar * Max Surke View author publications You can also search for this author

inPubMed Google Scholar * Lutz Ackermann View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS A.M.M. unravelled the photo-promoted

iron-catalysed C–H activation of imines, conducted the mechanistic studies, explored the substrate scope assisted by T.v.M. and M.S., and wrote the paper with revisions provided by the other

authors. M.S. performed the Grignard studies. L.A. conceived and directed the research programme and revised the paper. CORRESPONDING AUTHOR Correspondence to Lutz Ackermann. ETHICS

DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. PEER REVIEW PEER REVIEW INFORMATION _Nature Catalysis_ thanks Brian Patrick and the other, anonymous, reviewer(s)

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institutional affiliations. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary Methods, Figs. 1–52, Tables 1–6 and References. SUPPLEMENTARY DATA 1 CIF file of the crystal

structure of compound 4A. SUPPLEMENTARY DATA 2 CIF file of the crystal structure of compound 4B. SUPPLEMENTARY DATA 3 CIF file of the crystal structure of compound 4C. SUPPLEMENTARY DATA 4

CIF file of the crystal structure of compound 4D. SUPPLEMENTARY DATA 5 CIF file of the crystal structure of compound 4E. SUPPLEMENTARY DATA 6 CIF file of the crystal structure of compound

4F. SUPPLEMENTARY DATA 7 CIF file of the crystal structure of compound 4G. SUPPLEMENTARY DATA 8 CIF file of the crystal structure of compound 5A. SUPPLEMENTARY DATA 9 CIF file of the crystal

structure of compound 5B. SUPPLEMENTARY DATA 10 CIF file of the crystal structure of compound 5C. SUPPLEMENTARY DATA 11 CIF file of the crystal structure of compound 6A. SUPPLEMENTARY DATA

12 CIF file of the crystal structure of compound 6B. SUPPLEMENTARY DATA 13 CIF file of the crystal structure of compound 6C. SUPPLEMENTARY DATA 14 CIF file of the crystal structure of

compound 8. SUPPLEMENTARY DATA 15 CIF file of the crystal structure of compound 10A. SUPPLEMENTARY DATA 16 CIF file of the crystal structure of compound 10B. SUPPLEMENTARY DATA 17 CIF file

of the crystal structure of compound _E_-3AA. SUPPLEMENTARY DATA 18 CIF file of the crystal structure of compound _E_-3AA″. SUPPLEMENTARY DATA 19 CIF file of the crystal structure of

compound _E_-3AJ. SUPPLEMENTARY DATA 20 CIF file of the crystal structure of compound _Z_-3EA. RIGHTS AND PERMISSIONS Springer Nature or its licensor (e.g. a society or other partner) holds

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temperature photo-promoted iron-catalysed arene C–H alkenylation without Grignard reagents. _Nat Catal_ 7, 273–284 (2024). https://doi.org/10.1038/s41929-023-01105-0 Download citation *

Received: 07 January 2023 * Accepted: 21 December 2023 * Published: 13 February 2024 * Issue Date: March 2024 * DOI: https://doi.org/10.1038/s41929-023-01105-0 SHARE THIS ARTICLE Anyone you

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