Reactions of thianthrene cation radical perchlorate (Th •+ ClO 4 − ) with R 4 Sn, R=methyl(Me), ethyl(Et), n-butyl(Bu), phenyl(Ph), and vinyl, in acetonitrile took place cleanly in the stoichiometric ratio Th •+ ClO 4 − /R 4 Sn 2:1. Oxidative cleavage of R 4 Sn occurred into R 3 Sn 3+ , that was assayed as R 3 SnCl, and the radical R • . The latter was primarily trapped as the 5-R-thianthreniumyl perchlorate, although abstraction of hydrogen atom from the solvent was significant in the cases of phenyl and vinyl radicals. Reactions of Th •+ ClO 4 − with RSnMe 3 , R=allyl, vinyl, Ph, Et, isopropyl (i-Pr), and tert-butyl (t-Bu), occurred with the same stoichiometry. Exclusive loss of the i-Pr, t-Bu, and allyl groups occurred. From reaction of Th •+ ClO 4 − with R 6 Sn 2 (R=Me and Ph) R 3 Sn + was formed exclusively; that is, the R 2 Sn 2 underwent two-electron oxidation