Syntheses and Chemistry of Bis‐ and Tris‐mercaptoborates

The preparation and chemistry of bis- and tris-mercaptoborates based on closo-B 12 and closo-B 10 structures is described. These species undergo a number of reactions such as halogenation and alkylation without changing the closo-borane core. Addition of the third di- methylsulfide substituent to the closo-boranes is thought to proceed via an unusual cationic intermediate.