Lanthanide Ion Complexes of Calixarenes. VIII. Bimetallic Lanthanide Complexes of p-t-Butylcalix[8]arene From Dimethylformamide Solutions

Abstract

Reaction of lanthanide(III) ion p- toluenesulfonates with a warm p-t- butylcalix [8] arene (L) solution in dmf/triethylamine ( dmf denotes N,N- dimethylformamide ), yields crystalline 2 : 1 Ln/ligand adducts, as dmf solvates: [Ln₂(L-6H)( dmf )₅]. xdmf , Ln = La, Pr, Lu and Eu (previously recorded; 2 phases) have been characterized by single-crystal X-ray studies; all phases are triclinic but only the praseodymium and α-form of the europium derivative are isostructural : Ln = La, Pr, α- Eu have Z = 2 formula units, while Ln = β- Eu , Lu have Z = 4. In all cases, the stoichiometry of the complex molecule is the same and the same as that of the dmso adducts recorded in the previous paper, with similar ligand dispositions.