MAGNETIC STUDY OF THE NOVEL POLYNUCLEAR COMPOUND [CU(II)(6-MERCAPTOPURINOLATE(2-))](N)

摘要

Chemical reactions between Cu(II) and 6-mercaptopurine, both in aqueous and in methanolic media, yield the novel amorphous polynuclear compound [Cu(II)(6-mercaptopurinolate)(2-)](n), which is also obtained from diverse Cu(II)-heterocyclic ligand competitive reactions. The kinetic and thermodynamic stabilities associated with the formation of this compound are inferred as remarkable. The spectroscopic data let us suggest the involvement of the exocyclic S(6) donor site and the N atoms in the imidazolic moiety of the deprotonated heterocyclic ligand in the coordination to Cu(II) atoms, forming a distorted bidimensional metallic network. The magnetic studies show the existence of very weak antiferromagnetic coupling in the solid sample. This system represents the first example of a 1:1 metal:6-mercaptopurinolate(2-) system with a d-type open shell metallic center. The magnetic study carried out also represents the first example of magnetic characterization for this type of polynuclear Cu(II) systems with the dianionic 6-mercaptopurine ligand. (C) 1997 Academic Press. [References: 23]