The dianion of the diacid (MIN1, Fig. ), formed a er the double α-deprotona on of the respec ve diacid 7, resembles the structure of dianion I4 (Scheme 4), which is the ul mate intermediate in the cycliza on to stellane deriva ve 1 (Scheme 1). The oxida on of MIN1 requires approximately 68 kcal mol -1 (2.9 eV), which is lower than the electron affinity of the iodine atom (3.06 eV) . This provides the driving force for the forma on of the distonic radical anionic intermediate MIN2 from dianion MIN1 in the presence of iodine. The DFT-and MP2-computed barriers for the cycliza on of MIN2 to stellane radical anion MIN3 through the transi on state (TS) are similar, ranging from 2 to 3 kcal mol -1 . It is noteworthy that MIN3 is a minimum in C2symmetry, represen ng a delocalized structure where spin and charge are equally distributed between two α-carbons. Remarkably, the strain increases en route the cycliza on process but is compensated by the energy gain from transannular bonding, where the key C•••C distance in the opened form MIN2 is approximately 3.8 Å compared to 2.9 Å in MIN3. Furthermore, the removal of the second electron to form the neutral stellane deriva ve MIN4 requires only ca. 53 kcal•mol -1 (2.29 eV) and can be easily accomplished in the presence of iodine. The reac on path was also explored in reverse, showing that the op mized neutral MIN4 converges to MIN3 a er re-op miza on as a radical anion, and vice versa if MIN3 is reop mized as a neutral. As the poten al around TS is rather flat we conclude that opened (MIN2) and closed (MIN3) radical anionic intermediates interchange so rapidly that the overall process is controlled predominantly by the oxida on of intermediates with iodine and rela ve stability of the stellane dicarboxylic acid (MIN4) determines the reac on outcome.