Cope Rearrangement

The Cope rearrangement is one of the [3,3]-sigmatropic rearrangement reactions of 1,5-hexadienes under heat conditions. The reaction mainly proceeds via a chair-like transition state; therefore, product stereochemistry can easily be expected. Taking advantage of this reaction, it is possible to form cycloheptadienes and cyclooctadienes from divinylcyclopropanes and divinylcyclobutanes, respectively. Furthermore, tandem reactions such as the synthesis of divinylcyclopropane and the Cope rearrangement have been reported. As alternative reactions, the aza-Cope rearrangement and oxy-Cope rearrangement are known and utilized in organic synthesis.