Structural studies of bis-(2,,6-diacetylpyridine-bis-(phenylhydrazone)) and X-ray structure of its Y(III), Pr(III), Sm(III) and Er(III) complex

摘要

Reaction of 2,6-bis(phenylhydrazone)pyridine with Ln(NO3)(3).6H(2)O nitrate (Ln Y, Pr, Sm and Er) produces mononuclear complexes. The crystal structures of [Ln(C23H19N5O2)(H2O)(NO3)] (Ln=Y or Er) and {[Ln(C23H19N5O2) (C23H20N5O2)](H2O)(2)((CH3)(2)SO)} (Ln=Pr or Sm) were determined. Coordination of the dianionic and the monoanionic ligands in the complexes is via the pyridyl nitrogen, hydrazino nitrogen and iminol oxygen. The crystal structures were determined.In the isostructuial complexes (Ln = Y, Er) the lanthanide ion have exactly the same coordination, being an irregular polyhedron with coordination number of eight.In the isostructural complexes (Ln=Pr, Sm) the lanthanide ion assumes a ten co-ordinated geometry for both metal ions. The coordination polyhedron around each lanthanide atom in both complexes is best described as a distorted bicapped square antiprism. (C) 2004 Elsevier Ltd. All rights reserved.