Abstract
The electron-transfer photochemistry of homochrysanthemol, 1, resulted exclusively in intramolecular "substitution" at the quaternary cyclopropane carbon, generating the five-membered cyclic ethers, 2 and 4. The alternative "addition" to the terminal carbon of the double bond, which would result in seven-membered cyclic ethers, 3 and 5, was not observed. Apparently, the five-membered transition state leading to 2 and 4 is significantly favored over the seven-membered one required for formation of 3 and 5. These results stand in interesting contrast to the previously established reaction pattern of chrysanthemol, 8, which is captured exclusively at the terminal vinyl carbon. The divergent regiochemistry of 1(*)(+) and 8(*)(+) (even though the tethers between vinylcyclopropane and alcohol functions differ only by a single CH(2) group) elucidates the principles governing the course of nucleophilic capture in radical cations.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.