Stereospecific Polymerization of Isoprene with Molecular and MCM‐48‐Grafted Lanthanide(III) Tetraalkylaluminates

Hard graft: Heterobimetallic peralkylated complexes [Ln{(μ-R)2(AlR2)}3] (R=Me, Et) can be exploited to study metal-size effects in “Ziegler Mischkatalysatoren”. Binary precatalyst system [Nd(AlMe3)4]/Et2AlCl and heterogenized single-component variants, such as [Nd(AlMe3)4]@Et2AlCl@MCM-48 (see picture) efficiently transform isoprene to a high-cis polymer (>99 %).