Synthesis, structure and reactivity of tert-butyldimethylsilylcyclopentadienyl lanthanide chlorides, including crystal structures of [(C5H4SiMe2But)2Gd(μ-Cl)]2 and (C5H4SiMe2But)2Er(SBT)(THF)

Reactions of anhydrous lanthanide trichloride with one or two equivalent of tert-butyldimethylsilylcyclopentadienyl (Cpt) potassium salt in THF afford mono(tert-butyldimethylsilylcyclopentadienyl)lanthanide dichloride complexes CptLnCl2(THF)3 [Ln=Y(1), Er(2)] and bis(tert-butyldimethylsilylcyclopentadienyl)lanthanide chlorides [Cpt2Ln(μ-Cl)]2 [Ln=Gd(3), Er(4), Yb(5)], respectively. DyCl3 reacts with KCpt in THF, followed by the treatment with two equivalents of C5H5Na to form the mixed-ring complex CptCp2Dy(THF) (6). Reaction of 4 with LiNPri2 and subsequently with one equivalent of PhNCO in THF give the PhNCO insertion product Cpt2Er[OC(NPri2)NPh](THF) (7). Complex 4 reacts with one equivalent of sodium benzothiazole-2-thiolate (NaSBT) to yield Cpt2Er(SBT)(THF) (8). Complexes 1–8 have been characterized by elemental analyses, infrared, 1H-NMR and mass spectroscopies. The molecular structures of 3 and 8 were determined by single crystal X-ray diffraction.