Selected 4-allenylcyclobutenones ring expand to the corresponding o-quinone methides upon thermolysis in refluxing toluene or benzene. These reactive intermediates were not isolated but trapped to give stable products. The reaction has synthetic potential as a route to highly-substituted phenols, benzofurans, and aryl analogs of hexahydrocannabinol. In addition, a unique rearrangement involving a methyl migration from silicon to carbon of ...
