Further Information
Literature
Related Reactions
Synthesis of oxetanes
Paterno-Büchi Reaction
The photochemical [2+2] cycloaddition of a carbonyl with an olefin to give an oxetane.
Mechanism of the Paterno-Buechi Reaction
The possible transitions (C=O) are shown below:
Once the carbonyl ground state has been photoexcited, either a singlet or triplet state may be formed:
n,π*-transition
Either type of transition (n,π* and π,π*) and electronic state (singlet, triplet) may participate in the first stage of this reaction, which is rationalized by invoking diradical intermediates:
Breaking of the new σ-bonds requires more energy, and the reverse reaction is not possible using same light frequency.
Recent Literature
The photocatalytic reactions of benzoylformate esters with alkenes can be
directed toward either Paternò-Büchi cycloadditions or allylic functionalization
reactions under conditions favoring energy transfer or electron transfer,
respectively.
J. Zheng, X. Dong, T. P. Yoon,
Org. Lett., 2020, 22, 6510-6515.
Paternò-Büchi Reactions of Silyl Enol Ethers and Enamides
F. Vogt, K. Jödicke, J. Schröder, T. Bach, Synthesis, 2009,
4268-4273.