Synthesis, spectroscopic studies and reactivity of η6-arene derivatives of titanium(IV)

Abstract

Halide abstraction from TiX 4 by AlX 3 in the presence of some aromatic hydrocarbons afforded the η 6-arene complexes of titanium(IV) of formula [TiX 3( η 6-arene)]AlX 4 (arene = 1,3,5-Me 3C 6H 3, X  Cl, Br; arene = 1,2,4,5-Me 4C 6H 2, X  Cl; arene = Me 6C 6, X  Cl, Br, I). The corresponding chloro complexes of 1,4-Me 2C 6H 4, 1,2,3,-Me 3C 6H 3 and 1,2,4-Me 3C 6H 3 were characterized in solution by 13C NMR spectroscopy. Arene displacement from [TiCl 3( η 6-arene)][AlCl 4] occurs with THF or TICp (Cp  C 5H 5 −) to afford TiCl 4(THF) 2 or CpTiCl 3, respectively. The titanium(IV)-arene complexes efficiently promote the hydrogen-deuterium exchange of the ring protons between C 6D 6 and C 6H 6− n Me n .