Term: aza-di-π-methane rearrangement
https://doi.org/10.1351/goldbook.AT07329

Definition:
Photochemical reaction of a 1-aza-1,4-diene or a 2-aza-1,4-diene in the triplet excited state to form the corresponding cyclopropylimine.

Note: The @R05194@ formally amounts to a 1,2-shift of the imino group and 'bond formation' between the C(3) and C(5) carbon atoms of the azadiene skeleton. 1-Aza-1,4-@D01699@ also undergo the @R05194@ to cyclopropylimines using electron-acceptor and electron-donor @S05610@ via radical-@C00907@ and radical-@A00358@ intermediates, respectively. 2-Aza-1,4-@D01699@ rearrange to N-vinylaziridines on @I03255@ using electron-acceptor sensitizers. In this instance the reaction amounts to a 1,2-shift of the alkene unit and 'bond formation' between the C(1) and C(3) carbon atoms of the azadiene skeleton. AT07329.png

Related Terms:
1) di-π-methane rearrangement (http://doi.org/10.1351/goldbook.D01745).
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) dienes (http://doi.org/10.1351/goldbook.D01699).
6) cation (http://doi.org/10.1351/goldbook.C00907).
7) anion (http://doi.org/10.1351/goldbook.A00358).
8) irradiation (http://doi.org/10.1351/goldbook.I03255).
9) photochemical reaction (http://doi.org/10.1351/goldbook.P04585).
10) sensitizers (http://doi.org/10.1351/goldbook.S05610).
11) triplet excited state (http://doi.org/10.1351/goldbook.T06503).

Image: Rearrangement reaction (https://goldbook.iupac.org/img/inline/AT07329.png) 

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 305 (https://doi.org/10.1351/pac200779030293)

Citation: 'aza-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.AT07329

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