The synthesis and characterisation, including X-ray diffraction study, of [Th{η-C 5 H 3 (SiMe 3 ) 2 } 3 ]; the first thorium( III ) crystal structure

Reduction of [ThCp″2Cl2][Cp″=η-C5H3(SiMe3)2] with Na–K in PhMe yields [ThCp″3], which is monomeric in the solid state, as determined by X-ray crystallography, and is the first crystalline tri-η-cyclopentadienylmetal complex, 〈Th–C(η-)〉 2.80(2)Å.