Cyclopentadienyl vs Indenyl Substituents. Organolanthanide Complexes and Biscarborane Compounds Derived from a Versatile Ligand, Me2Si(C9H7)(C2B10H11)

Abstract

A versatile compound, Me2Si(C9H7)(C2B10H11) can be conveniently converted into the monoanion [Me2Si(C9H6)(C2B10H11)]Na, the dianion [Me2Si(C9H6)(C2B10H10)]Na2, and the trianion [Me2Si(C9H6)(C2B10H11)]K3 by treatment with 1 equiv or excess amounts of NaH or K metal in THF, respectively. Reaction of LnCl3 with 1 equiv of [Me2Si(C9H6)(C2B10H11)]Na in THF gave dichloride complexes [η5-Me2Si(C9H6)(C2B10H11)]LnCl2(THF)3 (Ln = Nd (1), Er (2)). They can further react with another equivalent of [Me2Si(C9H6)(C2B10H11)]Na to afford monochloride complexes [η5-Me2Si(C9H6)(C2B10H11)]2LnCl(THF)2 (Ln = Ce (3), Nd (4), Sm (5), Er (6)), which can also be prepared by treatment of LnCl3 with 2 equiv of [Me2Si(C9H6)(C2B10H11)]Na in THF. 4 reacts with excess NaH in THF to produce [Na(THF)6][{η5:σ-Me2Si(C9H6)(C2B10H10)}2Nd] (7), which can also be prepared from the reaction of NdCl3 with 2 equiv of [Me2Si(C9H6)(C2B10H10)]Na2 in THF. Treatment of 2 with 2 equiv of K metal at room temperature yielded [η5:η6-Me2Si(C9H6)(C2B10H11)]Er(THF)2 (8). Reaction of 6 with 1 equiv of NaH afforded [{η5:σ-Me2Si(C9H6)(C2B10H10)}{η5-Me2Si(C9H6)(C2B10H11)}]Er(μ-Cl)Na(THF)3 (9), which can also be prepared from the reaction of 2 with 1 equiv of [Me2Si(C9H6)(C2B10H10)]Na2 in THF. Treatment of 9 with a mixture of 1 equiv of NaOH and excess NaH in THF generated the dinuclear complex [Na2(THF)11][{η5:σ-Me2Si(C9H6)(C2B10H10)}{μ-η5:σ-(C9H6)SiMe2O}Er]2 (10). Treatment of Me2Si(C9H7)(C2B10H11) with excess NaH in THF under UV-light followed by reaction with 1 equiv of LnCl3 resulted in the isolation of unprecedented biscarborane compounds [LnCl2(THF)5][μ-CH-(closo-C2B10H11)-nido-CB10H11] (Ln = Er (11), Y (12)). All of these complexes were characterized by various spectroscopic and elemental analyses. The solid-state structures of 7 and 9−12 were confirmed by single-crystal X-ray analyses.