Bis(tetramethylcyclopentadienyl)titanium Chemistry. Molecular Structures of [(C₅HMe₄)(μ-η¹:η⁵-C₅Me₄)Ti]₂and [(C₅HMe₄)₂Ti]₂N₂

Thermolysis of bis(tetramethylcyclopentadienyl)-stabilized titanium(III) compounds (C5HMe4)2TiR (R = Me (2), Ph (3)) yields, in marked contrast with the bis(pentamethylcyclopentadienyl) analog, the dimeric product [(C5HMe4)(μ-η1:η5-C5Me4)Ti]2 (4), with a bridging metalated tetramethylcyclopentadienyl ligand. The hydride (C5HMe4)2TiH (5), synthesized by hydrogenolysis of 2 or 3, reacts with N2 to form the dinuclear Ti(II) dinitrogen compound [(C5HMe4)2Ti]2N2 (8). Under a dynamic vacuum, the dinitrogen complex 8 loses the N2 ligand to give the titanocene (C5HMe4)2Ti (10). The molecular structures of both 4 and 8 were determined by X-ray diffraction methods.