Metal-catalyzed σ-bond rearrangement

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.^[1] [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.^[2]