Term: de Mayo reaction
https://doi.org/10.1351/goldbook.DT07354

Definition:
Photochemical process leading to the formation of cyclobutanols by cycloaddition of an alkene to a 1,3-dicarbonyl-enol. The enol originates in most cases from the tautomerization of a 1,3-dicarbonyl compound. The products of the de Mayo reaction are susceptible to undergo a retro-aldol ring opening resulting in the formation of 1,5-dicarbonyl compounds. DT07354.png

Related Terms:
1) cycloaddition (http://doi.org/10.1351/goldbook.C01496).
2) tautomerization (http://doi.org/10.1351/goldbook.T06253).
3) retro (http://doi.org/10.1351/goldbook.R05370).

Image: Not defined (https://goldbook.iupac.org/img/inline/DT07354.png) 

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 322 (https://doi.org/10.1351/pac200779030293)

Citation: 'de Mayo reaction' 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.DT07354

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