1,4,7-Trithiacyclononane (9S3) is a tridentate thioether ligand that can be used to prepare complexes with a wide variety of transition metal ions. These complexes often possess exceptional electronic and redox properties. 9S3 ligand reacts with palladium metal ion to form palladium(II) thioether complex, which is used as a catalyst in the C-H activation reactions. Manganese complex of 9S3 ligand is employed as a catalyst for the oxidation of olefins, alkanes, and alcohols.