Metal-ion-catalyzed σ-bond rearrangement

The metal-catalyzed σ-bond rearrangement is a collection of chemical reactions that occur with highly strained organic compounds are treated with metals like Ag⁺, Rh(I), or Pd(II) reagents. [2+2] ring openings are sometimes observed:

These rearrangements proceed via oxidative addition of strained rings. Such processes are related to the activation of cyclopropanes by transition metals.

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