Electrocycloreversion of benzocyclobutenols promoted by photoinduced electron transfer

Article abstract of DOI:10.1016/0040-4039(96)01152-5

Benzocyclobutenols 1 undergo electron-transfer induced electrocycloreversion to generate o-quinodimethane intermediates E-4 and Z-4, which then tautomerize to benzophenones 2. Evidence for the intermediates is provided by the trapping experiments and the laser flash photolysis experiments.