• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.150-153
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• 1986

Co-sensitized photooxygenation of 1,1-diphenyl-2-vinylcyclopropane (VCP-DPh) with 9,10-dicyanoanthracene and biphenyl in oxygen-saturated acetonitrile solution produced 3,3-diphenyl-5-vinyl-1,2-dioxolane as the major product. The same photoproduct was obtained by acetone sensitized photooxygenation in oxygen-saturated acetone solution. However, VCP-DPh remained intact when directly irradiated with DCA or irradiated with Rose Bengal to generate singlet oxygen. A mechanism involving a cosensitizer radical cation and sensitizer radical anion is proposed.

• Journal of Photoscience
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• v.10 no.1
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• pp.1-7
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• 2003

The results of recent work on the dye-sensitized photooxygenation of sulfides is discussed. In the case of dialkyl sulfides, the weakly bonded adduct initially formed with singlet oxygen (the persulfoxide) decays unproductively unless protonation by an acid (an alcohol or a carboxylic acid) facilitates its conversion to the sulfoxide. The effect is proportional to the strength of the acid (eg., less than 0.1 % chloroacetic acid in benzene is sufficient for maximal efficiency) and corresponds to general acid catalysis, suggesting that protonation of the persulfoxide occurs. On the other hand, with sulfides possessing an activated hydrogen in ${\alpha}$ position (eg., benzyl and allyl sulfides), hydrogen transfer becomes an efficient process in aprotic media and yields a S-hydroperoxysulfoniumm ylide, possibly arising from a conformation of the persulfoxide that is different from the one protonated in the presence of acids. Calculations on some substituted sulfides support this hypothesis. This process, which leads to C-S bond fragmentation with formation of an aldehyde, may be viewed as a general method for the preparation of aryl and heteroaryl aldehydes. In this effort, mechanistic studies offered new hints on the structure of the intermediate persulfoxide.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.65-65
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• 1999

• Bulletin of the Korean Chemical Society
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• v.9 no.1
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• pp.68-69
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• 1988

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.112-113
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• 1988

• Journal of the Korean Chemical Society
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• v.22 no.6
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• pp.417-422
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• 1978

Rather than undergo photooxygenation, the Z-configuration benzalpyrrolinones (Z-2, Z-4) photoisomerized to the E-configuration isomers under direct or sensitized irradiation. Rose bengal sensitized photochemical stereoisomerzation of benzalpyrrolinones (Z-2, Z-4 and E-2) with monochromatic light (at 557 nm, excitation of rose bengal only) showed that the triplet of benzalpyrrolinones was involved in the photoisomerization, since oxygen inhibited the photoisomerization.

• Journal of the Korean Chemical Society
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• v.23 no.6
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• pp.396-401
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• 1979

Measuring the reaction rate of bilirubin and oxodipyrromethenes with singlet oxygen, we have found oxodipyrromethenes to be better singlet oxygen trapping agents than diphenyl-isobenzofuran, the best such agent known so far. The photooxygenation rates of bilirubin and the model compounds, oxodipyrromethenes approached the diffusion control threshold. A new oxodipyrromethene is synthesized.

• Journal of the Korean Chemical Society
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• v.24 no.2
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• pp.146-149
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• 1980

Oxodipyrromethene was degraded by a self-photosensitized reaction, similar to the degradation of bilirubin by other investigators. Photodegradation of oxodipyrromethene was faster in methanol-d4, in which the life time of singlet oxygen is longer, than in methanol. It was slower in a solvent which contained a singlet oxygen quencher. Moreover, the products from sensitized and unsensitized reactions are same.