439146-34-6Relevant articles and documents
Discovery and optimization of new chromium catalysts for ethylene oligomerization and polymerization aided by high-throughput screening
Jones, David J.,Gibson, Vernon C.,Green, Simon M.,Maddox, Peter J.,White, Andrew J. P.,Williams, David J.
, p. 11037 - 11046 (2005)
High throughput screening (HTS) of a 205 member Schiff base salicylaldimine ligand library derived from salicylaldehydes bearing bulky ortho-substituents, i.e., 9-anthracenyl, 1,4,5,8-tetramethylanthracenyl or triptycenyl, reacted in-situ with (p-tolyl)CrCl2(thf)3, identified two new classes of highly active chromium based systems for the Oligomerization and polymerization of ethylene, respectively. The polymerization system comprises bidentate ortho-substituted anthracenyl Schiff bases bearing small primary or secondary alkyl imine substituents. The Oligomerization catalysts are based upon tridentate orthotriptycenyl-substituted Schiff bases with pyridylmethyl or quinolyl substituents. Validation tests confirmed polymerization productivities of up to 3000 g·mmol-1h-1bar-1 for the polymerization catalyst systems while the oligomerization catalysts gave productivities up to 10 000 g·mmol-1h-1bar -1. Key catalyst precursors have been characterized by X-ray crystallography.