Synthesis and derivatisation of ceric tris(tert-butoxy)siloxides.

Metathesis reactions involving cerium(iv) complexes are generally hampered by a high tendency for reduction to the favoured trivalent state and a preference for ligand redistribution. Heteroleptic ceric Ce[OSi(OtBu)]Cl(thf) is easily obtained from the oxidation of CeOSi(OtBu) with trityl chloride, while the absence of thf triggers formation of homoleptic Ce[OSi(OtBu)]. Ce[OSi(OtBu)]Cl(thf) engages in salt metathesis reactions with the alkali metal alkoxides KOCH and KOtBu, forming CeOSi(OtBu)(thf), but experiences an extensive reductive ligand redistribution with the methylating agent ZnMe.