C–H Bond Activation by σ‑Bond Metathesis as a Versatile Route toward Highly Efficient Initiators for the Catalytic Precision Polymerization of Polar Monomers

Rare earth metals show high activities toward C–H bond activation of heteroaromatic substrates and even methane. In this work, we demonstrate the suitability of this synthetic approach to rare earth metallocenes and show the applicability of the resulting complexes as highly efficient initiators for rare earth metal-mediated group transfer polymerization. Bis­(cyclopentadienyl)­(4,6-dimethylpyridin-2-yl)­methyl lanthanide complexes exhibit unprecedented initiation rates for rare earth metal-mediated dialkyl vinylphosphonate polymerization and facilitate an efficient initiation for a broad scope of Michael acceptor-type monomers.