Organic Chemistry

Programmed Polyene Cyclization Enabled by Chromophore Disruption

Authors

Abstract

A versatile polyene cyclization strategy was developed that exploits conjugated -ionyl derivatives. Photomediated disruption of the extended -system within these chromophores unveils a contra-thermodynamic polyene that engages in a Heck-type cyclization to afford [4.4.1]-propellanes. The connectivity of overbred polycycles generated from this process is controlled by the position of the requisite C–Br bond. Thus, compared to conventional biomimetic polyene cyclization, this approach allows for complete control of regiochemistry and facilitates incorporation of both electron-rich and electron-deficient (hetero)aryl groups. This strategy was successfully applied to the total synthesis of taxodione and salviasperanol, two isomeric abietane-type diterpenes that previously could not be prepared along the same synthetic pathway.

Version notes

Noah M. Bartfield was erroneously left off as an author. This version recognizes his contribution to the work.

Content

Thumbnail image of JHF 9 R1.2F.pdf

Supplementary material

Thumbnail image of JHF9 SI R1.1F-combined.pdf
Supproting Information
Detailed experimental procedures and characterization data