- The (usually intramolecular) transfer of an atom or group during the course of a molecular rearrangement.
-
The movement of a bond to a new position, within the same
molecular entity
is known as 'bond migration'. Allylic rearrangements, e.g.
exemplify both types of migration.
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1141