An easy synthetic route to heteroleptic samarium monoalkoxides for ring-opening polymerization initiators.: Molecular structures of [(C5Hi-Pr4)SmI(THF)2]2, SMI2Ot-Bu(THF)4, and (C4Me4P)2SmOt-Bu(THF)

Samarium(III) monoalkoxides bearing two, one, or no cyclopentadienyl type spectator ligands are easily synthesized by monoelectronic oxidation with tert-butylperoxide of the corresponding samarium(II) precursors. These monoalkoxides are single-site initiators for ring-opening polymerization.