Preparation, thermodynamic and structural studies of some malononitrile derivatives and their complexes

The thermodynamic functions for the formation of Mn (II), Fe (II), Co (II), Ni (II) and Cu (II) complexes with two derivatives of malononitrile were determined. An endothermic behaviour was observed. The complexes are stabilized mainly by the entropy changes. The structure of malonitriles prepared was characterized using IH and C-13 NMR spectroscopy. Probable composition of the complexes was inferred from conductometric and photometric titrations, and infrared and thermogravimetric studies. The electrical property of both derivatives was followed.