Term: di-π-methane rearrangement
https://doi.org/10.1351/goldbook.D01745

Definition:
photochemical reaction of a molecular entity comprising two π-systems, separated by a saturated carbon atom (a 1,4-diene or an allyl-substituted aromatic analogue), to form an ene- (or aryl-) substituted cyclopropane. D01745.png

Note: The @R05194@ formally amounts to a 1,2 shift of one ene group (in the diene) or the aryl group (in the allyl-aromatic analogue) and 'bond formation' between the lateral carbons of the non-migrating @M03968@.

Related Terms:
1) aza-di-π-methane rearrangement (http://doi.org/10.1351/goldbook.AT07329).
2) di-π-silane rearrangement (http://doi.org/10.1351/goldbook.DT07360).
3) oxa-di-π-methane rearrangement (http://doi.org/10.1351/goldbook.O04359).
4) rearrangement (http://doi.org/10.1351/goldbook.R05194).
5) moiety (http://doi.org/10.1351/goldbook.M03968).
6) photochemical reaction (http://doi.org/10.1351/goldbook.P04585).
7) molecular entity (http://doi.org/10.1351/goldbook.M03986).

Image: Not defined (https://goldbook.iupac.org/img/inline/D01745.png) 

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 325 (https://doi.org/10.1351/pac200779030293)

Citation: 'di-π-methane rearrangement' 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.D01745

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