Rare-Earth-Silyl ate-Complexes Opening a Door to Selective Manipulations.

The reactions of a number of rare-earth (RE) trichlorides and an oligosilanylene diide containing a siloxane unit in the backbone in DME are described. The formed products of the type [(DME)·K][(DME)·RE(Cl){Si(SiMe)SiMe}O] (RE = Y, La, Ce, Pr, Sm, Tb, Dy, and Er) are disilylated dichloro metalate complexes and include the first examples of Si-La and Si-Pr compounds as well as the first structurally characterized example of a Si-Dy complex. A most intriguing aspect of the synthesis of these complexes is that they offer entry into a systematic study of the still largely unexplored field of silyl RE complexes by the possibility of ligand exchange reactions under preservation of the Si-RE interaction. This was demonstrated by the conversion of [(DME)·K][(DME)·RE(Cl){Si(SiMe)SiMe}O] to [(DME)·K][CpY{Si(SiMe)SiMe}O].