A @[email protected] in which the principal product is indistinguishable (in the absence of @[email protected]) from the principal reactant. The term includes both 'degenerate @[email protected] rearrangements' and reactions that involve @[email protected] transfer of atoms or groups ('degenerate @[email protected] rearrangements'): both are degenerate @[email protected] The occurrence of degenerate rearrangements may be detectable by @[email protected] or by dynamic NMR techniques. For example: the [3,3]@[email protected] of hexa-1,5-diene (Cope @[email protected]):
Synonymous but less preferable terms are '@[email protected]', 'permutational @[email protected]', 'isodynamic @[email protected]', '@[email protected]'.
See also:
molecular rearrangement
valence isomer
PAC, 1994, 66, 1077. (Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)) on page 1104 [Terms] [Paper]