Half-sandwich rare-earth-metal derivatives bearing pyrrolidinyl-functionalized cyclopentadienyl ligand: synthesis, characterization and catalysis in syndiospecific polymerization of styrene

Substitution Effects in Highly Syndioselective Styrene Polymerization Catalysts Based on Single-Component Allyl ansa-Lanthanidocenes: An Experimental and Theoretical Study

“…2,3,4,5,6,7 Besides, the independent discovery of the first neutral rare-earth metal complex {Me2C(C5H4)(Flu)}Nd(η 3 -C3H5)(THF) (I) (Flu = 9-fluorenyl), which acts as a single-component catalyst, 8,9,10,11 and the first cationic rare-earth metal catalytic system (C5Me4SiMe3)Sc(CH2SiMe3)2(THF)/[Ph3C][B(C6F5)4] (II) 12 for syndiospecific polymerization of styrene, has led to the subsequent description of a large range of related rare-earth based competent catalyst systems. 13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30 sPS is a very industrially promising material due to its high melting point (ca. 270 °C), high crystallinity, low dielectric constant and good chemical and heat resistances.…”

Recent Advances in Rare Earth Complexes Bearing Allyl Ligands and Their Reactivity towards Conjugated Dienes and Styrene Polymerization

“…Contrary to what advanced for 4Lu, the smaller Cpcent-RE-N bite angle in pyridyl-Cp complexes 3RE, along with a Scheme 6. Allylic rare earth complexes used for styrene polymerization [33][34][35].…”

“…Styrene, when polymerized by coordination-insertion polymerization, can give rise to PS under three different forms: isotactic, syndiotactic, or atactic (Scheme 5). The pyrrolidinyl-functionalized half-sandwich complexes (C5Me4SiMe2NC4H8)RE(η 3 -C3H5)2 (10RE, RE = Sc, Y, Lu, Scheme 6) were synthesized by reacting RECl3 with one equivalent of C5Me4SiMe2-NC4H8Li followed by the addition of two equivalents of C3H5MgCl in THF at room temperature [33]. The 1 H NMR spectra of the three complexes indicated the fluxional allyl ligand in solution, with one sharp doublet signal for the terminal allylic protons and one multiplet for the central allylic protons.…”

Lanthanides and actinides: Annual survey of their organometallic chemistry covering the year 2013

“…The half-sandwich rare-earth metal derivatives bearing a pyrrolidinylfunctionalized cyclopentadienyl ligand shown in Scheme 73 have been investigated as catalysts for styrene polymerization. [50]. Similarly, the pyridyl-functionalized indenyl rare-earth metal bis(silylamide) complexes shown in Scheme 92 have been investigated as styrene polymerization catalysts.…”

“…of allylmagnesium chloride, C 3 H 5 MgCl, or LiN(SiHMe 2 ) 2 in THF at room temperature afforded the half-sandwich rare-earth metal bis( 3 -allyl) complexes (C 5 Me 4 SiMe 2 NC 4 H 8 )Ln( 3 -C 3 H 5 ) 2 (Ln = Sc, Y, Lu) and the half-sandwich rare-earth metal bis(silylamide) complexes (C 5 Me 4 SiMe 2 NC 4 H 8 )Ln[N(SiHMe 2 ) 2 ] 2 (Ln = Sc, Y, Lu), respectively, as illustrated in Scheme 73. All these complexes were fully characterized by elemental analyses, FT-IR spectroscopy, NMR spectroscopy and X-ray crystallography [50].…”