Rare-Earth Metal Bis(alkyl) Complexes Bearing the FluCH2?THF Ligand: Synthesis, Structures, and Catalysis toward Polymerizations of Conjugated Dienes
writer：Yutong Han, Zhaohe Liu, Zhongfu Zhao, Bo Liu,* and Dongmei Cui
keywords：OLEFIN POLYMERIZATION， LIVING POLYMERIZATION， ANILIDO-PHOSPHINIMINE REACTIVITY， ISOPRENE COPOLYMERIZATION， MONONUCLEAR
source：期刊
Issue time：2022年
A series of constrained-geometry-con?guration (CGC) rare-earth metal complexes bearing the ligand ?uorenylmethylene-tetrahydrofuranyl (η5 -FluCH2-THF)Ln(CH2SiMe3)2(THF) (Ln = Y, 1; Lu, 2) have been synthesized by the alkane elimination reaction between the FluCH2-THF ligand and the rare-earth metal trialkyls and fully characterized by nuclear magnetic resonance and X-ray di?raction analyses. Complexes 1 and 2 are monomeric THF solvates, in which the CGC ligand adopts the η5 /κ1 bonding mode with the central metals via coordination of ?ve carbon atoms from the ?uorenyl fragment and the tetrahydrofuranyl oxygen atom. Upon activation with AliBu3 and [Ph3C][B(C6F5)4], complex 1 showed high activity toward conjugated diene polymerization, to a?ord up to 98.5% cis-1,4-polybutadiene and 69.0% 3,4-unit-enriched polyisoprene. The reason behind this was elucidated.