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

Chemical reactions between Cu(II) and 6-mercaptopurine, both in aqueou s and in methanolic media, yield the novel amorphous polynuclear compo und [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 c ompound are inferred as remarkable. The spectroscopic data let us sugg est the involvement of the exocyclic S(6) donor site and the N atoms i n the imidazolic moiety of the deprotonated heterocyclic ligand in the coordination to Cu(II) atoms, forming a distorted bidimensional metal lic network. The magnetic studies show the existence of very weak anti ferromagnetic 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 typ e of polynuclear Cu(II) systems with the dianionic 6-mercaptopurine li gand. (C) 1997 Academic Press.