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Formation of low-valent Fe$^0$ and Fe$^I$ species in Fe-catalyzed cross-coupling chemistry: key role of ate-Fe$^{II}$ intermediates

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HAL Id: cea-02339541

https://hal-cea.archives-ouvertes.fr/cea-02339541

Submitted on 30 Oct 2019

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Formation of low-valent Fe

0

and Fe

I

species in

Fe-catalyzed cross-coupling chemistry: key role of

ate-Fe

II

intermediates

Lidie Rousseau, C. Herrero, M Clémancey, A Imberdis, G Blondin, J.-M

Latour, G Lefèvre

To cite this version:

Lidie Rousseau, C. Herrero, M Clémancey, A Imberdis, G Blondin, et al.. Formation of low-valent Fe

0

and Fe

I

species in Fe-catalyzed cross-coupling chemistry: key role of ate-Fe

II

intermediates.

GECOM-CONCOORD 2019, May 2019, Erquy, France. �cea-02339541�

(2)

GECOM-CONCOORD 2019 - Erquy,

19-24 mai

Formation of low-valent Feo and Fe' species in Fe-catalyzed

cross-coupling chemistry: key role of ate-Fe" intermediates

L.

Rousseaua,b, C. HerreroC

, M. Clémanceyd, A. Imberdisb, G. Blondind, J.-M. Latourd, G. Lefèvre*a,b

a : LCMCE, NIMBE, CEA, CNRS, Univ. Paris-Saclay, 91191 Gif, France

b : CSB2D, Institute of Chemistry for Life and Health Sciences, Chimie ParisTech, PSL University, CNRS, 75005 Paris, France;

C:

ICMMO, Univ. Paris-Saclay, 91405 Orsay, France;

d: LCBM, pmb, Univ. Grenoble Alpes, CEA, CNRS, 38000 Grenoble, France guillaume.lefevre@chimieparistech.psl.eu

Ate-iron(lI) species such as [Ar3Fe"]- (Ar = aryl) are key intermediates in Fe-catalyzed cross-coupling reactions between aryl Grignard reagents (ArMgX) and organic electrophiles.(1) They can be active species in the

catalytic cycle,(2) or lead to Feo and Fel oxidation states. These low oxidation states were shown to be catalytically active in some cases, but they mostly lead to unwished organic byproducts.!3,4)

This works relates a study of the evolution of [Ar3Fe"]- complexes towards Feo and Fel oxidation states, through

1H

NMR, EPR and 57Fe-Môssbauer spectroscopies, as weil as DFT calculations, so as to discuss the role of both steric parameters and spin states in the reduction processes. Such mechanistic insights give a betler understanding of iron-catalyzed C-C bond formation reactions, and can be exploited in the design of new ligands in order to selectively obtain a sole iron oxidation state in a catalytic process.

2-eleel,""

j

red. el. [Feo] no reduction of the metal n=3

t

Bime/allie

j

Monitoring: red. el. 1HNMR EPR [Fel] Mossbâuer

Figure 1: Pathways connecting ate-Fe" (Mes = 2,4,6-trimethylphenyl) species with Feo and Fel oxidation'states

[1] S. L. Daifuku, J. L. Kneebone, B. E. R. Snyder, M. L. Neidig, J. Am. Chem. Soc. 2015,137,11432

[2] P. B. Brenner, E. Carter, P. M. Cogswell, M. F. Haddow, J. N. Harvey, D. M. Murphy, J. Nunn, C. H. Woodall, R. B,

Bedford, Angew. Chem. Int. Ed. 2014, 53, 1804

[3] F. E. Zhurkin, M. D. Woodrich, X. Hu, Organometallics 2017,36,499

Figure

Figure  1:  Pathways connecting ate-Fe" (Mes  =  2, 4,6-trimethylphenyl) species  with  Feo and Fel oxidation 'states  [1]  S

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