Benzene can undergo photocycloadditions in three different ways, ortho, meta and para. Among these, meta-cycloadditions have received the most attention. Pyridones are well known for their propensity for [4+4] photocycloadditions with a broad selection of 1,3-dienes and 1,3-diene equivalents. In a mixed system designed to favor benzene–pyridone cycloaddition, the cycloaddition favors a para cycloaddition of the pyridone diene with the benzene. When the benzene has a substituent, cycloaddition can yield two cis/trans isomers. These highly strained molecules can undergo a thermal [3,3] rearrangement. A study of the chlorine and methoxy substituted benzene substrates will be discussed.

Para- and [4+4] photocycloadditions in mixed pyridone–benzene systems

Macromolecular Chemistry: The Second Century

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ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.