Photo-oxidation halocarbons

Photosensitized oxygenation of a-ketoketene mercaptals has been described and these give dioxetanols, which subsequently collapse to carboxylic acids. Photo-oxidation of the mesoionic compounds (63) and (64) gives ring-cleavage products via endoperoxides and irradiation of tetrathiatetracene and of its selenium analogue in halocarbon solvents leads to radical cation salts. 

In the presence of O2 and H2O, the photo-formed e and h react with these molecules on the titanium oxide surfaces to produce 02/ and OH radicals, respectively. These 02/ and OH radicals have a very high oxidation potential, inducing the complete oxidation reaction of various organic compounds such as toxic halocarbons, as shown in... 

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