Synthesis and structures of Ti(iii) and Ti(iv) complexes supported by a tridentate aryloxide ligand

Abstract

Titanium complexes of the tridentate aryloxide Me–L³⁻ [H₃(Me–L) = 2,6-bis(4,6-dimethylsalicyl)-4-tert-butylphenol] have been prepared. Reaction of TiCl₄ with 1 equivalent of H₃(Me–L) gave [Ti(Me–L)Cl]₂1. Recrystallization of 1 from THF resulted in formation of the THF adduct Ti(Me–L)Cl(THF)₂2. Treatment of 1 with [NEt₄]Cl in THF quantitatively gave [NEt₄][Ti₂(Me–L)₂Cl₃] 3. Complex 1 was reduced with 2 equivalents of potassium to produce the Ti(III) complex [Ti(Me–L)(DME)]₂4. Structures of 1, 2, 3 and 4 have been determined by X–ray analyses. For 1, 2 and 4, the Me–L ligand assumes a U-conformation. In the case of 3, it is coordinated in an S-conformation.