Synthesis of rare-earth-metal-in-cryptand dications, [Ln(2.2.2-cryptand)]2+, from Sm2+, Eu2+, and Yb2+ silyl metallocenes (C5H4SiMe3)2Ln(THF)2†
Abstract
Cp′2Ln(THF)2 metallocenes (Cp′ = C5H4SiMe3) react with 2.2.2-cryptand (crypt) to form Ln2+-in-crypt complexes, [Ln(crypt)(THF)][Cp′3Ln]2 (Ln = Sm, Eu) and [Yb(crypt)][Cp'3Yb]2, that contain Ln2+ ions surrounded only by neutral ligands. A bimetallic, mixed-ligand metallocene/opened-crypt complex of Sm2+, [Sm(C16H32N2O6-κ2O:κ2O′)SmCp′′2], was obtained by KC8 reduction of Cp′′2Sm(THF) [Cp′′ = C5H3(SiMe3)2] in the presence of crypt.