Term: photocyclization
https://doi.org/10.1351/goldbook.PT07450

Definition:
intramolecular photochemical process leading to carbo- or hetero- cyclic ring systems by formation of one new single bond, either by a concerted process (e.g., electrocyclization) or by multi-step processes such as Norrish–Yang reaction, photoinduced electron transfer processes, Yang photocyclization and others.

Related Terms:
1) intramolecular (http://doi.org/10.1351/goldbook.I03130).
2) concerted process (http://doi.org/10.1351/goldbook.C01234).
3) norrish–yang reaction (http://doi.org/10.1351/goldbook.NT07427).
4) photoinduced electron transfer (http://doi.org/10.1351/goldbook.P04617).
5) yang photocyclization (http://doi.org/10.1351/goldbook.YT07500).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 388 (https://doi.org/10.1351/pac200779030293)

Citation: 'photocyclization' 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.PT07450

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