title: Multidimensional reaction coordinate for the excited-state H-atom transfer in perylene quinones: importance of the 7-membered ring in hypocrellins A and B.
abstract: The excited-state intramolecular H-atom transfer reactions of hypocrellins B and A are compared by using time-resolved absorption and fluorescence upconversion techniques. The hypocrellin B photophysics are well described by a simple model involving one ground-state species and excited-state forward and reverse H-atom transfer with a nonfluorescent excited state. We suggest that excited-state conformational changes are coupled to the H-atom transfer in hypocrellin B just as gauche/anti changes are coupled to the H-atom transfer in hypocrellin A.
authors.affiliation: Department of Chemistry, Iowa State University, Ames 50011, USA.
authors.forename: A
authors.initials: A
authors.lastname: Datta
authors.forename: A V
authors.initials: AV
authors.lastname: Smirnov
authors.forename: J
authors.initials: J
authors.lastname: Wen
authors.forename: G
authors.initials: G
authors.lastname: Chumanov
authors.forename: J W
authors.initials: JW
authors.lastname: Petrich
mesh_terms: D007700:Kinetics; D015394:Molecular Structure; D010569:Perylene / Q000031:analogs & derivatives* / Q000737:chemistry; D019800:Phenol; D010777:Photochemistry; D017319:Photosensitizing Agents / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry*; D012997:Solvents; D013053:Spectrophotometry
chemical_list: D017319:Photosensitizing Agents; D011809:Quinones; D012997:Solvents; D019800:Phenol; D010569:Perylene; C048388:hypocrellin A; C064522:hypocrellin B