Term: intra-
https://doi.org/10.1351/goldbook.I03128

Definition:
The prefix for an elementary reaction or some part thereof indicating that the bond(s) undergoing primitive changes form part of a ring in the transition state of the elementary reaction. This prefix is used for nonpericyclic processes only and is replaced by 'cyclo' for pericyclic processes.

Related Terms:
1) elementary reaction (http://doi.org/10.1351/goldbook.E02035).
2) transition state (http://doi.org/10.1351/goldbook.T06468).

Source: PAC, 1989, 61, 23. 'System for symbolic representation of reaction mechanisms (Recommendations 1988)' on page 34 (https://doi.org/10.1351/pac198961010023)

Citation: 'intra-' 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.I03128

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