Titanium Complexes Stabilized by a Sulfur‐Bridged Chelating Bis(aryloxo) Ligand as Active Catalysts for Olefin Polymerization

Abstract

AbstractThe mixed‐ligand complexes [Ti2(μ‐OR)2(OR)2(κ3‐tbop)2] (1a) for R = Me and (1b) R = Et were prepared by the reaction of Ti(OR)4 and H2tbop {H2tbop = 2,2′‐thiobis[4‐(1,1,3,3‐tetramethylbutyl)phenol]} in methanol. Treatment of 1a and 1b with AlMe3 led to the substitution of terminal alkoxy groups to create the organometallic compounds [Ti2(μ‐OR)2(κ3‐tbop)2(Me)2] (2a) for R = Me and (2b) for R = Et. Controlled hydrolysis of 2b causes the evolution of methane and the formation of the titanoxane compounds [{Ti2(μ‐OEt)2(κ3‐tbop)2}2(μ‐O)2]·2CH2Cl2 (3). Structures of 1a, 1b, 2a, 2b, and 3 were confirmed by NMR spectroscopy; 1b and 3 were further investigated with X‐ray crystallography. Compounds 1a, 1b, 2a, and 2b were supported on MgCl2 and when activated with aluminum alkyls, found to effectively polymerize ethylene. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)