2,6-Diiminopyridine Iron(II) Dialkyl Complexes. Interaction with Aluminum Alkyls and Ethylene Polymerization Catalysis

Bis(pyridine)iron dialkyl complexes FeR2Py2 (R = CH2Ph, CH2CMe2Ph, and CH2SiMe3) react with 2,6-diiminopyridine ligands, affording the corresponding organoiron complexes. The complex Fe(CH2SiMe3)2(C5H3N-2,6-(C(N-mesityl)Me)2, 4a, becomes an active ethylene polymerization catalyst upon treatment with Al or Zn alkyls. A catalytically active 1:1 Fe/Al adduct has been detected in solution by 1H and UV−vis spectroscopies.