Term: minimum structural change, principle of
https://doi.org/10.1351/goldbook.08186

Definition:
Principle that a chemical reaction is expected to occur with a minimum of bond changes or with a minimum redistribution of electrons (although more complex reaction cascades are also possible).

Example:  [image] where the transfer of <span title="substance">\(\ce{Cl}\)</span> is accompanied by migration of only one carbon, rather than a more extensive molecular rearrangement involving migration of three methyls.

Example: Array

Image: minimum structural change principle of (https://goldbook.iupac.org/img/inline/08186.jpg) 

Source: PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 465 (https://doi.org/10.1515/pac-2018-1010)

Citation: 'minimum structural change, principle of' 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.08186

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