Term: migratory aptitude
https://doi.org/10.1351/goldbook.M03923

Definition:
The term is applied to characterize the relative tendency of a group to participate in a rearrangement. In nucleophilic rearrangements ( migration to an electron-deficient centre), the migratory aptitude of a group is loosely related to its capacity to stabilize a partial positive charge, but exceptions are known, and the position of hydrogen in the series is often unpredictable.

Related Terms:
1) rearrangement (http://doi.org/10.1351/goldbook.R05194).
2) migration (http://doi.org/10.1351/goldbook.M03920).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1141 (https://doi.org/10.1351/pac199466051077)

Citation: 'migratory aptitude' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03923

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