Term: elimination
https://doi.org/10.1351/goldbook.E02038

Definition:
The reverse of an addition reaction or transformation. In an elimination two groups (called eliminands) are lost most often from two different centres (1/2/elimination or 1/3/elimination, etc.) with concomitant formation of an unsaturation in the molecule (double bond, triple bond) or formation of a new ring. If the groups are lost from a single centre (α-elimination, 1/1/elimination) the resulting product is a carbene or a 'carbene analogue'.

Related Terms:
1) α-elimination (http://doi.org/10.1351/goldbook.A00007).
2) addition reaction (http://doi.org/10.1351/goldbook.A00133).
3) transformation (http://doi.org/10.1351/goldbook.T06446).
4) carbene (http://doi.org/10.1351/goldbook.C00806).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1112 (https://doi.org/10.1351/pac199466051077)

Citation: 'elimination' 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.E02038

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