Heterometallic Hydride Complexes of Rare-Earth Metals and Ruthenium through C-H Bond Activation

The reaction of rare-earth monoalkyl complexes [Cp(2)Ln(CH2SiMe3)(thf)] (Cp = cyclopentadienyl; Ln = Y, Lu) with the ruthenium hydride complex [HRu(dmpe)Cp] (dmpe = bis(dimethylphosphino)ethane) gave the corresponding bimetallic hydride complexes [Cp(2)Ln(mu-H)(mu-eta(1):eta(5)-C5H4)Ru(dmpe)] (Ln = Y (1a), Lu (1b)). One carbon atom of the Ru-bound Cp ligand bridges to the Ln atom in these complexes. The linkage is formed via a C H bond activation step. The reaction of la with diphenylacetylene led to the formation of [Cp2Y(mu-H){mu-(Ph)CC(Ph)(C5H4)}Ru(dmpe)], which indicates that the Y C a-bond is significantly more reactive than the Y-H-Ru bond. The reaction of bis(alkyl) complexes [Ln(CH2SiMe3)(2)(OC6H3(Bu-t)(2)-2,6)(thf)(2)] (Ln = Y, Lu, tBu = tert-butyl) with [HRu(dmpe)Cp] gave the dimeric products [(OC6H3(Bu-t)(2)-2,6)Ln(mu-H)(mu-eta(1):eta(5)-C5H4){kappa C-3,P,P'-CH2(Me)P-(CH2)(2)PMe2}Ru](2) (Ln = Y, Lu) by double C-H bond activation. The complexes were characterized by NMR spectroscopy, X-ray crystal structure analysis (XRD), and elemental analysis.