BIMETALLIC LANTHANIDE COMPLEXES WITH LANTHANIDE TRANSITION-METAL BONDS - MOLECULAR-STRUCTURE OF (C4H8O)(C5H5)2LU-RU(CO)2(C5H5) - THE USE OF LA-139 NMR-SPECTROSCOPY

The reactions of Cp2LuCl(THF) (1), {Cp''2Lu(mu-Cl)}2 (2), Cp*2Lu(mu-Cl)2Na(THF)2 (3), and LaI3(THF)3 with the salt Na[CpRu(CO)2] yielded heterobimetallic complexes (THF)nX2LnRu(CO)2Cp (Ln = Lu, n = 1, X = C5H5 (Cp) (4)or 1,3-(Me3Si)2C5H3 (Cp'') (5); n = 0, X = C5Me5 (Cp*) (6); Ln = La, n = 3, X = I (9)). The structure of 4 has been established by X-ray crystal analysis (P2(1)/n, a = 14.083 (2) angstrom, b = 8.347 (2) angstrom, c = 17.331 (2) angstrom, beta = 106.98-degrees, Z = 4, d(calc) = 2.04 g/cm3, R = 0.0373, R(w) = 0.0369). Complex 4 is the first example of a compound characterized by X-ray crystal structure in which there is a direct lanthanide-metal bond (Lu-Ru 2.955 (2) angstrom) without the additional coordination through bridging ligands. According to IR and NMR evidence the Ln-Ru bond in 4-6 and 9 is stable in solutions. Reactivity of cluster complexes toward HCl, H2O, HgCl2, i-Pr2CO, MeI, H-2, CO, PhMeSiH2, and Me3SiC=CSiMe3 has been investigated. Reaction of 5 with HCl and H2O yielded 2 and {Cp''2Lu(mu-OH)}2 (10), structures of which have been determined by X-ray crystal analysis (2: P1BAR, a = 10.744 (3) angstrom, b = 11.821 (2) angstrom, c = 12.966 (3) angstrom, alpha = 71.54 (1)degrees, beta = 85.32 (2)degrees, gamma = 74.83 (1)degrees, Z = 1, d(calc) = 1.38 g/cm3, R = 0.0202, R(w) = 0.0206; 10: P2(1)/n, a = 15.638 (6) angstrom, b = 15.787 (2) angstrom, c = 12.188 (1) angstrom, beta = 99.06-degrees, Z = 2, d(calc) = 1.37 g/cm3, R = 0.0280, R(w) = 0.0298). Both 2 and 10 possess similar dimeric structures with a pair of bridging ligands Cl or OH, respectively. Average distances are 2.62 angstrom for Lu-Cl and 2.26 angstrom for Lu-O. La-139 spectroscopy has been used for studying Schlenk type equilibria for both cyclopentadienyl complexes Cp3La, CpLaI2, and {Cp''2La(mu-Cl)}2 and bimetallic complexes X2La-Ru(CO)2Cp.