High tetraalkylaluminate fluxionality in half-sandwich complexes of the trivalent rare-earth metals

Steric factors govern the formation of half-sandwich complexes (C5Me4R)Ln[N(SiHMe2)2]2 according to acid–base reactions utilising Ln[N (SiHMe2)2]3(thf)2 and substituted cyclopentadienes. Subsequent trimethylaluminium-promoted silylamide elimination produces the first halfsandwich bis(tetramethylaluminate) complexes (C5Me4R)Ln(AlMe4)2.