New Sulphur-Oxygen Mixed-Donor ligand N,N’-dimethyl-piperazine-3-oxo-2-thione (Me2pipto) and its Ni(II) and Fe(II) complexes

Structural and electronic features of the novel title sulfur-oxygen donor ligand Me2pipto (1), are discussed in comparison with those of the corresponding dithione ligand Me2pipdt. A tuning of the electronic and coordination properties of the ligand, relatable to the soft/hard power of the donor atoms, is achieved. Coordination properties have been checked towards Ni(II) and Fe(III) cations obtaining [Ni(Me2pipto)3](BF4)2 (2) and [Fe(Me2pipto)3](BF4)2 (4) complexes, which show significant differences when compared with the corresponding reaction products when using Me2pipdt.