Divergent Fe-Mediated C-H Activation Paths Driven by Alkali Cations
Vincent Wowk1, Alexis K Bauer2, Aleksa Radovic2
1CNRS, Institute of Chemistry for Life and Health Sciences, CSB2D, Chimie ParisTech, PSL University, 75005 Paris, France.
Abstract:
The association of the ferrous complex FeIICl2(dmpe)2 (1) with alkali bases M(hmds) (M = Li, Na, K) proves to be an efficient platform for the activation of Ar-H bonds. Two mechanisms can be observed, leading to either Ar-FeII species by deprotonative ferration or hydrido species Ar-FeII-H by oxidative addition of transient Fe0(dmpe)2 generated by reduction of 1. Importantly, the nature of the alkali cation in M(hmds) has a strong influence on the preferred path. Starting from the same iron precursor, diverse catalytic applications can be explored by a simple modulation of the MI cation. Possible strategies enabling cross-coupling using arenes as pro-nucleophiles, reductive dehydrocoupling, or deuteration of B-H bonds are discussed.
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