Cope, Oxy-Cope and Anionic Oxy-Cope Rearrangements

The Cope rearrangement,1 discovered in 1940 by Arthur C. Cope early in his outstanding career, comprises the thermal rearrangement of 1,5-dienes to isomeric 1,5-dienes (equation 1). Today it is recognized as the prototype all-carbon member of a large family of related rearrangements which include the Claisen, aza-, thia- and phospho-Claisen rearrangements, rearrangements of allylic esters, and a number of other variations collectively classified as 3,3-sigmatropic rearrangements.