Advances in PNP-ligated rare-earth-metal complexes: Reactivity and catalytic performances

Document Type : Mini Review

Authors

1 Petrochina Petrochemical Research Institute, Petrochina Company Limited, Beijing 102206, China

2 Provincial Key Laboratory of Polyolefin New Materials, College of Chemistry & Chemical Engineering, the Northeast Petroleum University, Daqing 163318, China

Abstract

Due to the large ionic radius and high electro-positivity nature, rare earth metal complexes are difficult to stabilize and undergo pathways like ligand redistribution and intramolecular C-H activation. To solve such problems and retain reactive versatility, rare earth complexes supported by a variety of tridentate PNP pincer ligands have been explored. Such complexes can serve as perfect precursors for preparing ultra-active rare earth species containing two metal-carbon bands, let alone Ln=N and Ln=P multiple bonds. In addition, the combined stability and activity of the cation rare earth mediates made them the best catalysts for the polymerization of olefins and other non-polar hydrocarbon monomers, especially conjugated dienes. The practical utilization of rare earth metal catalysts for new materials production have also extensively explored by experts from the academic and industries. 

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