1,4,7-Trithiacyclononane


1,4,7-Trithiacyclononane, also called 9-ane-S3, is the thia-crown ether with the formula 3. This cyclic thioether is most often encountered as a tridentate ligand in coordination chemistry, where it forms transition metal thioether complexes.
9-ane-S3 forms complexes with many metal ions, including those considered hard, such as copper and iron. Most of its complexes have the formula 2+ and are octahedral. The point group of 2+ is S6.

Synthesis

This compound was first reported in 1977, and the current synthesis entails the assembly within the coordination sphere of a metal ion followed by decomplexation: