Involvement of titanocene and related species in the reduction of dinitrogen and olefins

Summary Four sequential products have been spectrally detected in the reduction by sodium of dicyclopentadienyltitanium(iv) dichloride: [(77-Cp)2TiCl]2, [(77-Cp)2-Ti]1-2, [(77-Cp)(C5H4)TiH]x, and (77-Cp)(C5H4)TiH2Ti- (C5H4)(77-Cp) ("stable titanocene"); the second of these reacts rapidly and reversibly with N2 to give a dark blue complex reducible to ammonia and appears to catalyse the cyclopentadienyltitanium-promoted rapid, room temperature-atmospheric pressure hydrogenation of olefins.