Silyl and siloxanediyl cyclopentadienyl titanium and zirconium complexes: synthesis and reactivity. X-ray molecular structure of [Zr{η5-C5H4SiMe2(μ-OH)}(μ-Cl)Cl2]2

Abstract

Chloro(dimethyl)silyl-η5-cyclopentadienyl group 4 metal complexes of the type [M(η5-C5H4Cl)Cl3] (Full-size image (<1 K)) react with thallium salts Tl(C5H4R) (R = H, SiMe3) to give mixed dicyclopentadienyl derivatives [M(η5-C5H4R)(η5-C5H4SiMe2Cl)Cl2], (M = Ti, R = H 3, R = SiMe34; M = Zr, R = H 5, R = SiMe36) in high yield. Hydrolysis of complexes 3 and 4 affords the dinuclear complexes [Ti(η5-C5H4R)Cl2]2{μ-[(η5-C5H4SiMe2)2O]}] [R = H 7, R = SiMe38) containing a siloxanyl bridge, by elimination of two equivalents of HCl. Reactions of complexes 1 with hydroxo containing reagents such as anhydrous LiOH and SiPh2(OH)2 give the derivatives [Ti(η5-C5H4SiMe2Cl)Cl2]2(μ-O)], 9 and Ti[μ-(η5-C5H4SiMe2OSiPh2-η1-O)]Cl2, 10 identified by analytical, spectrometric and spectroscopic data. Treatment of analogous complex 2 with water produces the dimeric monocyclopentadienyl zirconium trichloride adduct [Zr(η5-C5H4SiMe2OH)Cl3]2, 11. Compound 11 has been characterized by X-ray crystallography.