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The title reaction provides sulfoxides together with small amounts of the corresponding sulfones. [ABSTRACT FROM AUTHOR]

Review: 52 refs. [ABSTRACT FROM AUTHOR]

As the main source of atmospheric sulfate aerosol, the aqueous-phase oxidation of SO 2 has been of great concern. Traditionally, the aqueous-phase oxidation of SO 2 is considered a consumption process of atmospheric oxidation capacity; however, we report here that •OH radicals and other reactive oxygen species (ROS) can be generated in the photochemical reactions of bulk HSO 3 − solution. This •OH production pathway results in the fast sulfate formation in the photooxidation of dissolved SO 2. The photochemical process is determined to be pH-dependent in which sulfate formation is promoted by decreasing pH. Hence, a light - driven acidic positive feedback mechanism is proposed that the oxidation of dissolved SO 2 and the formation of •OH radicals have a synergistic promoting effect. These results indicate that the photochemistry of dissolved SO 2 could be a missing source of aqueous •OH radicals as well as sulfate at regional to global scales. [Display omitted] • Aqueous-phase photooxidation of SO 2 is an important sulfate formation pathway. • Acidity promotes rather than inhibits the aqueous-phase photooxidation of SO 2. • SO 2 is not only a consumer but also an initiator of reactive oxygen species. [ABSTRACT FROM AUTHOR]

HO-adduct radicals have been investigated and confirmed as the common initial intermediates in TiO2 photocatalysis and Fenton degradations of water-insoluble aromatics. However, the evolution of HO-adduct radicals to phenols has not been completely clarified. When 4-d-toluene and p-xylene were degraded by TiO2 photocatalysis and Fenton reactions, respectively, a portion of the 4-deuterium or 4-CH3 group (18-100 %) at the attacked ipso position shifted to the adjacent position of the ring in the formed phenols (NIH shift; NIH is short for the National Institutes of Health, to honor the place where this phenomenon was first discovered). The results, combined with the observation of a key dienyl cationic intermediate by in situ attenuated total reflectance FTIR spectroscopy, indicate that, for the evolution of HO-adduct radicals, a mixed mechanism of both the carbocation intermediate pathway and O2-capturing pathway occurs in both aqueous TiO2 photocatalysis and aqueous Fenton reactions. [ABSTRACT FROM AUTHOR]

TiO2 acts as a photocatalyst in the synergistic aerobic oxidation of aryl sulfides and benzylamines. [ABSTRACT FROM AUTHOR]

Review: 62 refs. [ABSTRACT FROM AUTHOR]

Highlights: [•] The actual role of F− in electron transfer reactions was investigated. [•] ESR results show that NDI − and NDI +–F− complex coexist in deaerated solvents. [•] The complexation of F− with the cation radical induced electron transfer reactions. [Copyright &y& Elsevier]

No two ways about it: In the photocatalytic deoxygenation of epoxides, the TiO2 particle concertedly transfers two stored electrons to generate a carbanion intermediate, which dissociates to the alkene product. This pathway ensures the higher alkene and stereoselectivity of the photocatalytic deoxygenation than those involving a single‐electron transfer. [ABSTRACT FROM AUTHOR]

Abstract: The photoreactions of aromatic compounds were investigated in aqueous dispersions of -FeOOH(goethite)/H2O2 at neutral pHs. It was found that aromatic compounds could undergo rapid decomposition and mineralization (even to 100% yield) in the presence of both -FeOOH and H2O2 under UV irradiation, and the degradation rates of the organics were related to their sorption ability of the surface of -FeOOH and were in the following order: salicylic acid ≈m-hydroxylbenzoic acid>p-hydroxylbenzoic acid≈benzoic acid>p-biphthalic acid>phenol>benzenesulfonic acid. The interactions of salicylic acid and benzenesulfonic acid with goethite were examined by Fourier transform infrared spectroscopy (FTIR), and electron spin resonance (ESR) was applied to detect the intermediate radicals formed in the photoreaction. The effect of pH and foreign ligands on the degradation of salicylic acid, decomposition of H2O2, and formation of dissolved iron was also examined. [Copyright &y& Elsevier]

The substitution and direct departure of the ipso ‐ H by OH radicals has long been considered as the main route for the hydroxylation of aromatic compounds in water. Detailed isotope ‐ labelled experiments showed that part of the ipso ‐ H shifted to the adjacent carbon in the aromatic ring and was retained in the final phenols (1,2 ‐ NIH shift). The results indicated that besides the common ipso ‐ substitution, a Wagner–Meerwein rearrangement of the carbocation intermediates also exists during the hydroxylation of aromatic compounds in H2O via advanced oxidation technologies. More information can be found in the Full Paper by Wanhong Ma, Jincai Zhao et al. on page   3568 in Issue 24, 2016 (DOI: 10.1002/asia.201601299). [ABSTRACT FROM AUTHOR]

Review: [28 refs. [ABSTRACT FROM AUTHOR]

It is shown, that the concerted multi-electron transfer is the dominant pathway in the photocatalytic deoxygenation of epoxides on a pristine TiO2 surface to give the corresponding alkenes. [ABSTRACT FROM AUTHOR]

The article presents the steps of the chemical equations involved in selective aerobic oxidation of amines.