A new family of sulfur-rich ligands based on the dmit system: synthesis and metal complexation of 4–4'-covalently bridged bis(2-thioxo-1,3-dithiol-5-thiolato) units

The synthesis of a new series of sulfur-rich ligands is reported. These compounds, which are related to the dmit2-(2-thioxo-1,3-dithiol-4,5-dithiolato) structure, comprise two 2-thioxo-1,3-dithiol-5-thiolato units linked by a bridging unit at the 4-position of the heterocycle via a dithioether spacer unit. Complexation reactions have been carried out on a variety of metal centres; dialkyl tin and gold(I) derivatives have been isolated and fully characterised. The X-ray crystal structure of an octahedral Ni(II) complex, involving two coordinating pyridine molecules, is presented.