Reaction of potassium 2,3,4,5-tetramethylphaspholide (KTmp) with SmCl3 in toluene at reflux did not yield [Tmp(3)Sm], but instead polymeric [(Tmp)(3)Sm . KCl .(C7H8)(1.5)](n) containing three Tmp ligands and KCl, so substitution of the last Sm-CI bond by Tmp seems stopped halfway. In contrast, the KCl-free phosphorus-bridged dimer [(Dmp)(3)Sm](2) (Dmp = 3,4-dimethylphospholyl) was obtained from KDmp and SmCl3 under the same conditions.