Nuclear magnetic resonance and infrared spectral studies on labile cis-dialkoxy-bis(acetylacetonato)titanium(IV) compounds

Abstract

The six-co-ordinated titanium(IV) compounds Ti(acac)₂X₂, where X = MeO, EtO, CF₃CH₂O, PrⁱO, BuⁿO, Bu^tO, ½[OCH₂CMe₂CH₂O], and Cl, have been studied in solution by infrared spectroscopy and variable-temperature n.m.r. All these compounds adopt the cis-configuration and undergo intramolecular rearrangement, and conventional kinetic parameters have been derived from the n.m.r. measurements. The preference for the cis-configuration is believed to be due to ligand → metal π-electron donation, and possible mechanisms for the proposed racemization of these labile compounds are discussed.