title: Photoreactions of p-quinones with dimethyl sulfide and dimethyl sulfoxide in aqueous acetonitrile. goerner@mpi-muelheim.mpg.de.
abstract: The effects of dimethyl sulfide (DMS) and dimethyl sulfoxide (DMSO) on the photoreactions of 1,4-benzoquinone (BQ), 1,4-naphthoquinone (NQ), 9,10-anthraquinone (AQ) and several derivatives in acetonitrile/water were studied. The observed triplet state of the quinones is quenched and the rate constant is close to the diffusion-controlled limit for reactions of most quinones with DMS and lower with DMSO. Semiquinone radical anions (Q*-) produced by electron transfer from sulfur to the triplet quinone were detected. For both DMS and DMSO the yield of Q*- is similar, being generally low for BQ and NQ, substantial for AQ and largest for chloranil. The specific quencher concentrations and the effects of quinone structure and redox potentials on the time-resolved photochemical properties are discussed.
authors.affiliation: Max-Planck-Institut für Bioanorganische Chemie, D-45413 Mülheim an der Ruhr, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Görner
mesh_terms: D000097:Acetonitriles; D004121:Dimethyl Sulfoxide; D007700:Kinetics; D010777:Photochemistry; D011809:Quinones / Q000737:chemistry*; D013440:Sulfides
chemical_list: D000097:Acetonitriles; D011809:Quinones; D013440:Sulfides; C004784:dimethyl sulfide; D004121:Dimethyl Sulfoxide; C032159:acetonitrile