Term: photo-Bergman cyclization
https://doi.org/10.1351/goldbook.PT07444

Definition:
intramolecular photoinduced cyclization of enediynes leading to aromatic compounds.

Notes:
0) The solvent plays a key role in the reaction efficiency and product distribution. The reversibility of the initial @P04585@ and competing radical vs ionic pathways dictate product distribution, in stark contrast to the thermal process.
1) This reaction is particularly attractive in molecular biology and molecular medicine. In particular, it permits the expeditious synthesis of core synthones of great diversity.

Related Terms:
1) photoreaction (http://doi.org/10.1351/goldbook.P04585).
2) intramolecular (http://doi.org/10.1351/goldbook.I03130).
3) cyclization (http://doi.org/10.1351/goldbook.C01494).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 384 (https://doi.org/10.1351/pac200779030293)

Citation: 'photo-Bergman cyclization' 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.PT07444

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