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Updated: Dec 27, 2025
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
The Impact of Macrocycle Conformation on the Taxadiene-Forming Carbocation Cascade: Insight Gained from Sobralene, a
Christopher J Hayes1, Matthew J Palframan1, Gerald Pattenden1
1School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
Abstract:
DFT calculations on the carbocation intermediates that connect the biosynthetic pathways leading to the sand fly pheromone sobralene and taxadiene have been made. Establishment of the conformation of the macrocyclic carbocation intermediate required to produce the (Z)-C8,C9 alkene bond in sobralene has identified new conformations of the verticillyl carbocation intermediates on the taxadiene biosynthetic pathway. These "sobralene-like" carbocation conformations provide an exothermic pathway to taxadiene and are validated by comparison to closely related structures (X-ray and NMR).
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