Displacement of a cyclopentadienyl ligand by a crown ether from a lanthanocene(II) [LnCp′′2]; crystal structures of the first cationic lanthanoid(II) complexes, [SmCp′′([18]-crown-6)][SmCp′′3]·0.5C6H6 and [YbCp′′([18]-crown-6)][Cp′′]·3C6H6 [Cp′′ = η5-C5H3(SiMe3)2-1,3]
Abstract
Treatment of [SmCp′′2] or [YbCp′′2] with [18]-crown-6 in benzene at ambient temperature yields the X-ray characterised, crystalline salts [SmCp′′([18]-crown-6)][SmCp′′3]· 0.5C6H6 1 and [YbCp′′([18]-crown-6)][Cp′′]·3C6H6 2; 1 with K in toluene affords [K([18]-crown-6)(η2-PhMe)2]- [SmCp′′3], also accessible from [SmCp′′2], K[Cp′′] and [18]-crown-6 in toluene [Cp′′ = η5-C5H3(SiMe3)2-1,3].