Boron-Substituted <i>o</i>‑Carboranetrithiol To Construct Trimeric Cobalt Clusters

A new o-carborane-based boron-substituted trithiol has been prepared via direct attachment of sulfur atoms to the B8/B9/B12 vertexes of o-carborane. On the basis of the trithiolate ligand, both the neutral 51 cluster valence electron (CVE) and the cationic 50-CVE trimeric cobalt clusters have been synthesized and structurally characterized. Electrochemical observations demonstrate that the 51-CVE cluster is electron-overloaded and readily undergoes one-electron oxidation to yield the thermodynamically stable 50-CVE species.