The crystal structure of tris (indenyl)uranium (β,β,β-trifluoroethanolate)

The title compound was obtained by reaction of the methyl tris(indenyl) uranium complex with trifluoroethanol. A crystal structure reveals that there are two symmetrically independent molecules in the unit cell. The coordination geometry about the uranium atom is a flattened tetrahedron with three π-bonded indenyl rings and one σ-bonded trifluoroethanol oxygen atom. The U---O bonds are remarkably short. The U---C distances indicate trihapto mode of bonding of the indenyl rings. Variation of the ligand X in the U(C₉H₇)₃X class of complexes would not affect the stereochemistry about the U atom.