Conjugated systems photooxidation

The reaction of singlet oxygen with conjugated double bonds usually is a 1,4-cycloaddition leading to formation of derivatives of the 1,2-diox -ene ring system. This can be achieved either by photooxidation or by reaction in the presence of triphenyl phosphite-ozone adduct (Section Vin.D.2), shown in equations 85 and 86 . ... 

The first communication about the Chl-sensitized water oxidation to 02 on the outer vesicle interface conjugated with Fe(CN)g reduction at the inner interface appeared in 1977 [42] (see System 2 in Table 1). However an attempt to reproduce this result was a failure [273]. Thus the possibility of water photooxidation in vesicular systems which contain either only Chi molecules or Chi molecules in combination with other photosynthetic pigments is still under discussion. However, embedding of the intact fragments of thylakoids in the vesicle membranes was found to provide the evolution of 02 from water upon illumination [273], But again this process was not conjugated with PET across the membranes. 

Sensitized photooxidation of benzhydrylidenecydobutane. Addition of singlet oxygen to a conjugated ethylenic-aromatic system. Determination of the structure of the bis-peroxide formed. Tetrahedron Letters, 13 (34), 3583-3586. 

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