PerspectiveChemistry

Corralling Positively Charged Molecular Radicals

+ See all authors and affiliations

Science  25 Jan 2013:
Vol. 339, Issue 6118, pp. 404-405
DOI: 10.1126/science.1233633

You are currently viewing the summary.

View Full Text

Summary

At the outset, the idea of forcing together multiple positive charges onto an organic molecule and ending up with a stable interlocked supramolecular structure seems destined for failure. Columbic repulsion forces usually extract an energetic penalty on adding an additional charge onto a highly charged molecule, and the organic radicals that would form with stepwise charge addition are likely to be unstable. On page 429 of this issue, Barnes et al. (1) show that counterintuitive thinking about this problem can reap rewards. They show that a [2]catenane molecule, in which two identical rings interlock noncovalently like links of a chain (2), displays a rich vein of electrochemical responses. This homocatenane (HC) can stabilize organic radicals and bear up to eight positive charges.