Aluminium zirconium (+3 and +4) heterometallic hydrido complexes of compositions [(η5-C5H5)2Zr(μ-H)]2(μ-H)AlCl2 and [(η5-C5H5)2ZrH(μ-H)2]3Al

The Zr(+3) complex of composition [Cp2Zr(μ-H)]2(μ-H)AlCl2 (8) and the Zr(+4) complex of composition [Cp2ZrH(μ-H)2]3Al (9) were isolated from solutions containing zirconocene(+4) and titanocene(+3) compounds and LiAlH4 and characterized by X-ray structural analysis. The basic structural element of 8 is the six-atom ring Zr2AlH3, in which the metal atoms are linked by ordinary hydrogen bridges. In the structure of 9, the Hbendo atom is off the bisector plane of the Cp2Zr fragment and the Al–H distances in the distorted octahedral environment of the aluminium atom are markedly different.