Organometallic chemistry of the actinides Part 4 - The chemistry of some tris(cyclopentadienyl) actinide complexes

Four tris(cyclopentadienyl)thorium(IV) or uranium(IV) complexes have been prepared by the ready transmetallation between MCl4, (M = Th or U) and the appropriate lithium cyclopentadienyl: [TnCp(3) " Cl]1 1, [(ThCp3Cl)-Cl-R] 2, [(ThCp3Cl)-Cl-tt] 3 and [UCp3 " Cl] 7. The treatment of [ThCp2 " Cl-2] or [(ThCp2Cl2)-Cl-tt] with the suitable lithium or potassium cyclopentadienyl yielded three mixed tris(cyclopentadienyl)thorium(IV) complexes: [ThCp2 "(Cp*)Cl] 4, [ThCp2tt(Cp)Cl] 5 and [ThCp2tt(Cp-B ")] 6. Compounds 1-7 have been characterised by C and H analyses, NMR spectra, EI mass spectra for 2, 3, 5 and 6, and for compounds 1-4 and 7 single-crystal X-ray diffraction. [Cp " = eta(5)-C5H3(SiMe3)(2)-1,3, Cp-R = eta(5)-C5H4CH(SiMe3)(2), Cp-tt = eta(5)-C5H3(SiMe2But)(2)-1,3, Cp* = eta(5)-C5Me5, Cp = eta(5)-C5H5, Cp-B " = eta(5)-C5H3Bu2t-1,3,Cp''' = eta(5)-C5H2(SiMe3)(3)-1,2,4]. (C) 1998 Elsevier Science S.A.