SYNTHESIS AND CHARACTERIZATION OF THE 1ST PENTAMETHYLCYCLOPENTADIENYL COMPLEX OF TRIVALENT EUROPIUM - [(C5ME5)EU(OCME3)(MU-OCME3)]2

EuCl3 reacts with 2 equiv of NaOCMe3 in THF to form a complex which analyzes as Eu3(OCMe3)7-Cl2(THF)2, 1. 1 reacts with KC5Me5 to form [(C5Me5)-Eu(OCMe3)(mu-OCMe3)(mu-OCMe3)]2, 2, in 60% yield. 2 was characterized by elemental analysis and spectroscopic methods and by X-ray crystallography. 2 crystallizes from Et2O at -34-degrees-C in the space group P2(1)/c with a = 12.847(3) angstrom, b = 17.329(5) angstrom, c = 18.670(4) angstrom, beta = 99.41(2)degrees, V = 4100-(2) angstrom3, and D(calcd) = 1.404 Mg/m3 for Z = 4. The two europium atoms and the two oxygen atoms of the bridging ligands form a plane which is perpendicular to the plane defined by the two C5Me5 ring centroids and the oxygen atoms of the terminal tert-butoxide ligands. The C5Me5 rings are arranged in a cis orientation around the (Me3-CO)Eu(mu-OCMe3)2Eu(OCMe3) central core.