Alternative Models of Iron and Cobalt Catalysts for Ethylene Oligomerization and Polymerization

1 Results Great progresses have been made in the field of transition metal-based complexes as catalytic precursors for olefin oligomerization and polymerization,in which the core subjects will remain as "know and how" to develop novel catalysts both in academic and industrial consideration.The key advantage of iron and cobalt catalyst for ethylene polymerization is to produce vinyl-type polyethylenes.Therefore following the pioneering works of bis(imino) pyridyl iron and cobalt catalyst by Brookhart[1] and Gibson[2] in 1998,there have been many contributions toward their derivatives’ complexes for the investigation of their catalytic behaviors.However,there are few examples successful good activity catalysts based upon new designed ligands such as monoiminopyridines[3],2-imino-1,10-phenanthrolines[4],2-benzimidazolylpyridines[5],2-quinoxalinyl-6-imino pyridines[6] and bimetallic complex[7].Those catalysts performed good to high catalytic activities towards ethylene oligomerization and polymerization,meanwhile most of them were first contributed with our efforts inspired by bis(imino)pyridyl metal catalyst.Herein we will present our results with designing pathways,and academic and industrial considerations.