Synthesis and Structure of Lanthanide Sandwich Complexes with Mixed Cyclooctatetraenyl and Chelating Substituted-indenyl Ligands

Two types of sandwich complexes (η⁵-MeOCH₂CH₂C₉H₆) Ln (η⁸-C₈H₈) (THF)_n [Ln=La (1), Nd(2), n=0; Sm(3), Dy (4) and Er (5). n = l] and (η⁵-C₄H₇OCH₂C₉H₆)Ln(η⁸-C₈H₈) (THF) [Ln = La (6), Nd(7). Sm(8). Dy (9) and Er (10)] were synthesized by the reactions of LnCl₃ with equivalent mole of K₂C₈H₈, followed by treatment with corresponding potassium salt of ether-substituted indenide. The molecular structures of 3 and 8 were determined by single crystal X-ray diffraction. (η⁵ -MeOCH₂CH₂C₉H₆) Sm (η⁸-C₈H₈) (THF) (3) monoclinic. Pt₁/c, a = 1.4793(3) nm, b = 0.8716 (2) nm, c = 1.6149 (3) nm, β = 98. 17(3), V = 2.0612(7) nm³, Z = 4, R(F)=0.0362. (η⁵-C₄H₇OCH₂C₉H₆)Sm(η⁸-C₈H₈)(THF) (8) orthorhombic. p2₁2₁2₁. a = 0.8754(2) nm, b = 1.1000(2) nm, c = 2.3117 (5) nm, V = 2.2260(8) nm³, Z=4, R(F) =0.0497.