ORGANOMETALLIC COMPOUNDS OF THE LANTHANIDES .59. (1,1'-(3-OXAPENTAMETHYLENE)DICYCLOPENTADIENYL)YTTRIUM AND -LUTETIUM 3,5-DIMETHYLPYRAZOLATES - X-RAY CRYSTAL-STRUCTURE OF [O(CH2CH2C5H4)2LN(MU-N2C3HME2)(MU-OH)LN(C5H4CH2CH2)2O] (LN = Y, LU)

The reaction of O(CH2CH2C5H4)2LnCl (Ln = Y, Lu) with NaN2C3HMe2 in tetrahydrofuran at room temperature generates the complexes O(CH2CH2C5H4)2Ln(N2C3HMe2) (Ln = Y (1), Lu (2)). The partial hydrolyses of 1 and 2 form [O(CH2CH2C5H4)2Ln(mu-N2C3HMe2)(mu-OH)Ln(C5H4CH2CH2)O] (Ln = Y (3), Lu (4)). The new compounds have been characterized by elemental analyses and IR and NMR spectra. The X-ray structural analyses of 3 and 4 show both to be tetragonal, space group P4(1)2(1)2, Z = 4, with a = 8.980 (2) angstrom, c = 37.403 (7) angstrom, and D(calcd) = 1.520 g cm-3 for 3 and a = 8.930 (5) angstrom, c = 36.868 (9) angstrom, and D(calcd) = 1.95 g cm-3 for 4. The structure was solved from 2294 observed reflections with F-degrees greater-than-or-equal-to 6-sigma-(F(o)) and refined to a final R factor of 0.0434 for 3 and from 2004 observed reflections with F(o) greater-than-or-equal-to a final R factor of 0.0323 for 4. The molecular structure shows the pyrazole and the hydroxyl groups both bridging with distances Y-N = 2.445 (5) angstrom, Y-O = 2.202 (2) angstrom, Lu-N = 2.392 (8) angstrom, and Lu-O = 2.154 (3) angstrom, whereas the oxygen atoms of the oxapentamethylene bridges are separated by 2.662 (4) angstrom from the Y atoms and 2.667 (7) angstrom from the Lu atoms.