The Stronger the Better: Donor Substituents Push Catalytic Activity of Molecular Chromium Olefin Polymerization Catalysts

The donor strength of bifunctional pyridine‐cyclopentadienyl ligands was altered systematically by the introduction of donating groups in the para ‐position of the pyridine. In the resulting chromium complexes an almost linear correlation between donor strength and the nitrogen‐chromium distance as well as the electronic absorption maximum is experimentally observed. The connection of electron‐donating groups in the ligand backbone leads to an...