Transmetalation in a Ce(III)-phosphoester Crystalline Coordination Polymer with an Exceptionally High Selectivity for Yb(III) and Lu(III).

A novel crystalline coordination polymer containing Ce and bis(4-nitrophenyl) phosphate (L), CeL , was synthesized and its unique transmetalation selectivities toward Yb and Lu in the lanthanide series were evaluated. The relatively large difference in transmetalation selectivity between the neighboring Tm and Yb species is noteworthy because the reactivities of heavy lanthanides are generally considerably similar. The structural strain of the polymeric framework is likely responsible for this unusual trend. Powder X-ray diffraction analysis indicated that, in the cases of only Yb and Lu , large differences in their ionic sizes compared to that of Ce in the parent framework may induce a structural strain after solid solution formation, while cleavage of the relatively weak Ce-O bond allows the formation of new Yb-O and Lu-O bonds with the incoming Yb and Lu , respectively. Structural phase transitions likely caused by the heterogeneous nucleation of the Yb- (or Lu-) type phase were also observed.