Discrete, Base‐Free, Cationic Alkaline‐Earth Complexes – Access and Catalytic Activity in the Polymerization of Lactide

Well‐defined, base free cations of zinc and the alkaline‐earth metals (Mg, Ca, Sr, Ba) supported by a multidentate phenolate ligand and stabilized by perfluorinated weakly coordinating counterions are readily available by simple procedures; the solid‐state structures of the magnesium and calcium derivatives were elucidated. Upon treatment with an excess of i PrOH, these complexes generate highly efficient binary catalytic systems for the immortal ring‐opening polymerization of L ‐lactide, yielding poly( L ‐lactide)s with controlled architectures and molecular features.