Paterno–Büchi reaction

https://doi.org/10.1351/goldbook.P04448
The @[email protected] of an electronically excited carbonyl group to a @[email protected] olefin yielding an oxetane.
P04448.png
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2258 [Terms] [Paper]