Preferred Label : degenerate rearrangement;
IUPAC definition : A molecular rearrangement in which the principal product is indistinguishable (in
the absence of isotopic labelling) from the principal reactant. The term includes
both 'degenerate intramolecular rearrangements' and reactions that involve intermolecular
transfer of atoms or groups ('degenerate intermolecular rearrangements'): both are
degenerate isomerizations. The occurrence of degenerate rearrangements may be detectable
by isotopic labelling or by dynamic NMR techniques. For example: the [3,3]sigmatropic
rearrangement of hexa-1,5-diene (Cope rearrangement): Synonymous but less preferable
terms are 'automerization', 'permutational isomerism', 'isodynamic transformation',
'topomerization'.;
Origin ID : D01559;
See also
A molecular rearrangement in which the principal product is indistinguishable (in
the absence of isotopic labelling) from the principal reactant. The term includes
both 'degenerate intramolecular rearrangements' and reactions that involve intermolecular
transfer of atoms or groups ('degenerate intermolecular rearrangements'): both are
degenerate isomerizations. The occurrence of degenerate rearrangements may be detectable
by isotopic labelling or by dynamic NMR techniques. For example: the [3,3]sigmatropic
rearrangement of hexa-1,5-diene (Cope rearrangement): Synonymous but less preferable
terms are 'automerization', 'permutational isomerism', 'isodynamic transformation',
'topomerization'.
