Tetranuclear rare earth metal polyhydrido complexes composed of "(C5Me4SiMe3)LnH2" Units. Unique reactivities toward unsaturated C-C, C-N, and C-O bonds.

The tetranuclear Lu and Y polyhydrido complexes [(C5Me4SiMe3)Ln(mu-H)2]4(THF) (Ln = Lu, Y) undergo novel multiple hydrogenation reactions with unsaturated organic compounds such as benzonitrile, gamma-butyrolactone, styrene, and 1,4-bis(trimethylsilyl)-1,3-butadiyne to afford a series of structurally characterizable polynuclear complexes that possess novel structures and are otherwise difficult to access. Most of these reactions are unprecedented and can be attributed to the unique cooperative effects of multiple active sites in the polyhydrido rare earth metal complexes.