title: Thermal and photochemistry of a pyrene dihydrodioxin (PDHD) and its radical cation: a photoactivated masking group for ortho-quinones.
abstract: Pyrene dihydrodioxins (1 and 2) have been synthesized and shown to be effective photochemical blocking groups for pyrene-4,5-dione (3). The mechanism of quinone release proceeds through the formation of a remarkably stable radical cation. Direct evidence is provided that this radical cation is not only thermally labile but also photochemically labile, and that both pathways lead to quinone extrusion. Once initiated with UV light, the pyrene quinone product serves as an electron-transfer photosensitizer for the further release of quinone with visible light.
authors.affiliation: Department of Chemistry, University of Cincinnati, Cincinnati, OH 45221-0172, USA.
authors.forename: Eric T
authors.initials: ET
authors.lastname: Mack
authors.forename: A Björn
authors.initials: AB
authors.lastname: Carle
authors.forename: J T-M
authors.initials: JT
authors.lastname: Liang
authors.forename: W
authors.initials: W
authors.lastname: Coyle
authors.forename: R Marshall
authors.initials: RM
authors.lastname: Wilson
mesh_terms: D002412:Cations; D004247:DNA / Q000737:chemistry / Q000187:drug effects; D004147:Dioxins / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry; D010777:Photochemistry; D011721:Pyrenes / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry*
chemical_list: D002412:Cations; D004147:Dioxins; D005609:Free Radicals; D011721:Pyrenes; D011809:Quinones; D004247:DNA