Inorganic Chemistry, Vol.55, No.13, 6643-6652, 2016
Synthesis and Structural Characterization of Lithium and Titanium Complexes Bearing a Bulky Aryloxide Ligand Based on a Rigid Fused-Ring s-Hydrindacene Skeleton
The bulky aryl alcohols, (Rind)OH (1) [Rind = EMind (a) and Eind (b)], based on the rigid fused-ring 1,1,3,3,5,5,7,7-octa-R-substituted s-hydrindacene skeleton were prepared by the reaction of (Rind)Li with nitrobenzene followed by protonation. The treatment of 1 with (BuLi)-Bu-n affords the lithium aryloxide dimers [(Rind)OLi(THF)](2) (2) or trimers [(Rind)OLi](3) (3), depending on the employed solvents (THF = tetrahydrofuran). The salt metathesis reaction of [(EMind)OLi(THF)](2) (2a) with TiCl4(THF)(2) leads to the formation of the mononuclear diamagnetic mono- and bis(aryloxide) Ti(IV) complexes, [(EMind)O]TiCl3(THF) (4a) and [(EMind)O](2)TiCl2 (5a). We also isolated a trace amount of the tris(aryloxide) Ti(IV) complex, [(EMind)O](3)TiCl (6a). The reaction between 2a and TiCl3(THF)(3) resulted in the isolation of the mononuclear paramagnetic mono- and bis(aryloxide) Ti(III) complexes, [(EMind)O]TiCl2(THF)(2) (7a) and [(EMind)O](2)TiCl(THF)(2) (8a). The discrete monomeric structures of the titanium complexes 4a, 5a, 6a, 7a, and 8a were determined by X-ray crystallography.