STUDIES ON ORGANOLANTHANIDE COMPLEXES .54. SYNTHESES AND X-RAY CRYSTAL-STRUCTURES OF BIS-(2-METHOXYETHYLCYCLOPENTADIENYL) RARE-EARTH IODIDES (MEOCH(2)CH(2)C(5)H(4))(2)LNI (LN=LA OR Y)

Reaction of bis-(2-methoxyethylcyclopentadienyl) rare earth chlorides with sodium iodide in tetrahydrofuran (THF) affords bis(2-methoxyethyl cyclopentadienyl) rare earth iodide complexes Cp(2)'LnI (Ln = La (1) o r Y (2); Cp' = MeOCH(2)CH(2)C(5)H(4)). They crystallize from THF-hexan e in the orthorhombic space group P2(1)2(1)2(1) with unit cell paramet ers a = 11.266(7) Angstrom, b = 12.350(10) Angstrom, c = 13.075(9) Ang strom and V = 1819(2) Angstrom(3) with Z = 4, for D-calc = 1.870 g cm( -3) for 1 and a = 12.237(4) Angstrom, b = 10.965(9) Angstrom, c = 12.8 05(1) Angstrom and V = 1718.3(8) Angstrom(3) with Z = 4 for D-calc = 1 .786 g cm(-3) for 2. The central metal Ln(3+) is coordinated by two Cp ' ring centroids, one iodine atom and two oxygen atoms of Cp', forming a distorted trigonal bipyramid. The La-O and Y-O bond distances avera ge 2.584 Angstrom and 2.48 Angstrom, respectively. The average La-C(et a(5)) bond length is 2.805 Angstrom and the Y-C(eta(5)) 2.68 Angstrom.