Bis(η5-cyclopentadienyl)titanium(II) in the gas phase:: Mass spectrometric and computational study of the structure and reactivity

Bis(η5-cyclopentadienyl)titanium(II), titanocene, was generated in the gas phase by a thermolysis of the titanocene complex with bis(trimethylsilyl)acetylene. This elusive compound was characterized by means of mass spectrometric methods. Density functional theory (DFT) calculations indicated that the triplet ground state titanocene is kinetically stable towards the unimolecular isomerizations. Based on a DFT calculated energetics, a mechanism of the formation of a titanocene dimer, was proposed, which was based on a formation of bis(η5-cyclopentadienyl)titanium hydride as a key intermediate.