Reduced oxidation state transition metal compounds useful as olefin polymerization catalysts

摘要

This invention is directed to reduced oxidation state Group 4-6 metal compounds, preferably the first row metals in those groups, suitable for activation as polymerization catalysts and characterized by comprising a substituted hydrotris(pyrazolyl)borate ancillary ligand and a plurality of single or multidentate uninegative ligands, excluding cyclopentadienyl ligands. The invention includes a polymerization process characterized by comprising contacting one or more monomers polymerizable by coordination or insertion polymerization under suitable polymerization conditions with these catalyst compositions.