Über Phenol‐Oxydationen

Photoredox reactivity of iron(III) phenolates in aqueous solution induced by ligand-to-metal charge transfer excitation

“…Iron(III) compounds are well known to oxidize various phenols to oligomeric or polymeric phenols [14,15]. The oxidation is preceded by the production of a red, blue or violet colour [3] which is diagnostic for the appearance of a phenolate !…”

“…The irradiation of this LMCT band leads to the formation of Fe(II). In analogy to the thermal oxidation of various phenols by Fe(III) [14,15] the photolysis is assumed to proceed according to the simple equation…”

“…The study of the photochemistry has been certainly hampered by the lack of well-defined and stable Fe(III) complexes with monodentate phenolate ligands in solution [13]. Frequently, Fe(III) compounds oxidize phenols in thermal reactions [3] which have been utilized for synthetic applications [14,15]. Nevertheless, under suitable conditions Fe(III) phenolates in aqueous solution should be stable enough in order to examine their photochemistry.…”

Molecular Cloning and Heterologous Expression of the Gene Encoding Dihydrogeodin Oxidase, a Multicopper Blue Enzyme from Aspergillus terreus

“…usunic acid, griseofulvin) of versatile origins has been recognized (2). Therefore, a variety of chemical and biological oxidizing systems has been developed for oxidations of phenolic compounds (3)(4)(5). However, model enzyme systems using laccase, tyrosinase, and peroxidase have been unable to reproduce regio-and stereospecificities, which are often observed in natural product biosynthesis.…”

The Oxidation of Organic Compounds by Active Manganese Dioxide

“…For example, .8-fluorosulfonylethylamines, e.g., 408 were dehydrogenated by active manganese dioxide to afford novel 2-aminoethenesulfonyl fluorides (409) (33%-96%). Whereas the indole derivative 411 could be prepared from indoline 410 by using 2,3-dichloro-5,6-dicyano-I.4-benzoquinone (DDQ) or palladium on carbon, the reaction of 410 (415) with active manganese dioxide depends very much on a solvent used. Thus.…”