The metal ion-catalyzed σ-bond rearrangement is a collection of chemical reactions that occur with highly strained organic compounds are treated with metal ions like Ag+, Rh(I), or Pd(II) based reagents.Michael B. Smith, Jerry March, March's Advanced Organic Chemistry, 5th Ed., John Wiley & Sons, Inc., 2001, p. 1459. [2+2] ring openings are sometimes observed:
At least some of these rearrangements proceed via oxidative addition of C-C. Such processes are related to the activation of cyclopropanes by transition metals.
See also Cyclobutane Cubane Cuneane Sigma-bond metathesis
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