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Published on: July 17, 2020
Photosensitized [2 + 2]-Cycloaddition of Complex Acceptor-Donor Combinations: A Regio/Diastereoselectivity Study
Jens Lefarth1, Axel G Griesbeck1
1Department of Chemistry, University of Cologne, 50939 Köln, Germany.
Abstract:
The photosensitized [2 + 2]-cycloaddition of chalcones, conjugated cyclopentenones, and cyclohexenones with electron-rich alkenes such as cyclic enolethers and polymethylated alkenes was investigated. While cyclic enones showed high regio- and stereoselectivity, acyclic enones resulted in a more complex product mixture containing dimers as well as four dominant regio- and diastereoisomers. This complex product mixture can be controlled by adjusting the reaction conditions such as sensitizer, solvents, or additives.
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