Synthesis of Various Nonbridged Titanium(IV) Cyclopentadienyl−Aryloxy Complexes of the Type CpTi(OAr)X₂and Their Use in the Catalysis of Alkene Polymerization. Important Roles of Substituents on both Aryloxy and Cyclopentadienyl Groups

Abstract

Various titanium complexes of the type Cp′Ti-(OAr)Cl 2 (Cp′ ) cyclopentadienyl; OAr ) aryloxy) could be prepared in high yields from Cp′TiCl 3 . These complexes show remarkable catalytic activities for alkene polymerization with MAO or Al i Bu 3 -Ph 3 CB(C 6 F 5 ) 4 : (C 5 -Me 5 )Ti(O-2,6-i Pr 2 C 6 H 3 )X 2 (X ) Cl (2b), Me (8b), CF 3 -SO 3 (9b)) showed the highest activities. The bond angle Ti-O-C (phenyl group) in 2b (173.0°) is significantly different from those for other complexes (162.3-163.1°).

Alkylmono(cyclopentadienyl)titanium Complexes Containing the 2,2′‐Methylenebis(6‐tert‐butyl‐4‐methylphenoxido) Ligand – Studies on the Nature of the Catalytic Species Present in α‐Olefin Polymerisation Processes

“…[7,15,20,23] For these samples, values of T g , T m and ∆H similar to those found with the 1/ MAO system [11] are observed. The use of the borane salt produces a decrease in the stereoselectivity of the process, as shown in Table 5 from an analysis of the degree of isotacticity in the samples by 13 C NMR spectroscopy.…”

Early–Late Heterobimetallic Alkoxides as Model Systems for Late‐Transition‐Metal Catalysts Supported on Titania

“…The distance from the titanium atom to the plane containing the cyclopentadienyl ring (2.065(2) ä) is normal for titanium complexes. [10] The Ti1 À O1 and Ti1 À O2 distances of 1.877(6) and 1.888(6) ä, respectively, are somewhat longer than those…”

Half-Titanocenes Containing Anionic Ancillary Donor Ligands: Effective Catalyst Precursors for Ethylene/Styrene Copolymerization

“…[80], but also exhibited efficient comonomer incorporations for copolymerization of ethylene with α-olefin [81][82][83], as well as with styrene [52][53][54][55][56] in the presence of MAO (Scheme 1). [52,53], whereas the Cp* analogue (4), which exhibited remarkable activities and comonomer incorporations in ethylene/α-olefin copolymerization [80][81][82][83], exhibited lower activities than 1-3 (Table 1) [52][53][54][55][56]. The resultant polymers are poly(ethylene-co-styrene)s exclusively without by-producing polyethylene and/or syndiotactic polystyrene [52,53].…”