A NEW METHOD FOR THE SYNTHESIS OF LN(N-ETA-6-C6ME6)(ALCL4)3 (LN=ND, SM, GD, YB), AND THE X-RAY CRYSTAL-STRUCTURE OF YB(ETA-6-C6ME6)(ALCL4)3.MEC6H5

A series of neutral eta6-C6Me6 complexes of lanthanide elements Ln(176 -C6Me6)(AlCl4)3 . MeC6H5(Ln = Nd, Sm, Gd, Yb) has been prepared direct ly in good yields from the reaction of LnCl3, AlCl3 and C6Me6 in tolue ne. The complexes have been characterized by elemental analysis, IR an d MS. Complex Yb(eta6-C6Me6)(AlCl4)3 - MeC6H5 (1) crystallizes from to luene in monoclinic space group P2(1)/a, with a = 12.203(4), b = 16.91 8(4), c = 18.718(3) angstrom, beta = 100.84(3)-degrees, V = 3795.37 an gstrom3, Z = 4, D(calcd) = 1.63 g cm-3. The X-ray diffraction study re veals that the Yb atom has distorted pentagonal bipyramidal geometry w ith C6Me6 in an apical position. The average Yb-C bond length is 2.86( 4) angstrom.