Darstellung und Kristallstrukturen von Salzen mit den Kationen [Cp* 2 Ti(H 2O) 2] 2+ und [Cp* 2Ti(OH)(H 2O)] + (Cp* = η 5-(CH 3) 5C 5)

Abstract

The reaction of Cp* 2TiCl 2 with AgCF 3SO 3 in tetrahydrofuran, in the presence of small amounts of water, yields the ionic complex [Cp* 2Ti(H 2O) 2](CF 3SO 3) 2 ( 1). The two salts, α-[Cp* 2Ti(OH)(H 2O)]CF 3SO 3 · H 2O ( 2) and [Cp* 2Ti(OH)(H 2O)]CF 3SO 3 · 2H 2O ( 4) can be isolated from aqueous solutions of 1. Crystallization from CHCl 3 yields a salt ( 3) with the same composition as 2, but having a different crystal structure (β modification). The [Cp* 2Ti(H 2O) 2] 2+ and the [Cp* 2Ti(OH)(H 2O)] + cations show the expected, nearly tetrahedral geometry. The TiOH 2 distances in the diaqua cation are 2.06(1) and 2.09(1) Å. The TiOH 2 and TiOH distances in the aqua-hydroxo cation are 2.11 and 1.87 Å, respectively (mean values from the three salts). The structures of 1 to 4 were determined by X-ray crystallography.