title: Primary photoreactions of the 3',5'-dimethoxybenzoin cage and determination of the release rate in polar media.
abstract: 3',5'-dimethoxybenzoin (DMB) is an important photoremovable protecting group. The primary photoreactions of DMB acetate and fluoride following photoexcitation by a subpicosecond laser flash were investigated by pump-probe spectroscopy. The primary photoproduct is identified as a preoxetane biradical intermediate that decays by different pathways depending on solvent polarity. In polar solvents (acetonitrile, water), the biradical decays by releasing acetate or fluoride with a lifetime of about 2 ns. Thus, DMB is an excellent protecting group for the investigation of fast processes such as protein folding.
authors: Departement Chemie, Universität Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland.
authors: Hassen
authors: H
authors: Boudebous
authors: Berta
authors: B
authors: Kosmrlj
authors: Boris
authors: B
authors: Sket
authors: Jakob
authors: J
authors: Wirz
mesh_terms: D000085:Acetates / Q000737:chemistry; D000097:Acetonitriles / Q000737:chemistry; D001573:Benzoin / Q000737:chemistry*; D001577:Benzophenones / Q000737:chemistry*; D002412:Cations; D002627:Chemistry, Physical / Q000379:methods*; D008027:Light; D008956:Models, Chemical; D010100:Oxygen / Q000737:chemistry; D010777:Photochemistry / Q000379:methods*; D010782:Photolysis; D017510:Protein Folding; D012997:Solvents / Q000737:chemistry; D013997:Time Factors
chemical_list: D000085:Acetates; D000097:Acetonitriles; D001577:Benzophenones; D002412:Cations; D012997:Solvents; D001573:Benzoin; D010100:Oxygen; C032159:acetonitrile