Singlet oxygen sensitizer

Table 3. Singlet Oxygen Yields for Singlet Oxygen Sensitizers...

FIGURE 14.5 Rate of decay of 02 against ZEA concentration in air-saturated solutions of DPPC unilamellar liposomes using RB as singlet oxygen sensitizer (a similar, but less marked, effect is observed with PBA as sensitizer). 

Conventional singlet oxygen sensitizers such as Thiazine dyes, 2 and 3, have been reported to promote Wagnerova Class II electron-transfer photooxygenations.60 For example, the participation of singlet oxygen in the reaction depicted in Fig. 9... 

Hecht S, Erechet JMJ. Light-driven catalysis within dendrimers designing amphiphilic singlet oxygen sensitizers. J Am Chem Soc 2001b 123 6959-6960. 

As indicated above, considerable efforts in research and development have been deployed into the development of insoluble singlet oxygen sensitizers. Although, rose bengal chemically bound to chloromethylated copolymer of styrene and di vinyl benzene [14, 84] (and commercialized as Sensitox ) has shown excellent results as far as its light stability in solid matrices is concerned [85], the sensitizer is suffering, in addition to the drawbacks of the... 

Benzophenone (BP) sensitized photooxidation of phenothiazine leads mainly to the formation of products A and B (17). In view of the many data available from the literature and from our own experiments the published interpretation needs, however, some revision provided 3H-phenothiazine-3-ones are not products of a singlet oxygen reaction with ground state phenothiazine (c.f. methylphenothiazine), formation of products A and B implies two different oxidation mechanisms. Since singlet oxygen sensitization by benzophenone (Equations 10 to 12) is known to be very inefficient, reaction sequence (10), (13), (14), and (9)... 

Various compounds are used as singlet oxygen sensitizers. 

The results of several control experiments made it clear that polymer rose bengal was an authentic singlet oxygen sensitizer.1 Photooxidation of typical singlet oxygen acceptors in non-polar... 

It was our intention when this new work began to outline, more fully, the effect of the polymeric structure on the effectiveness of rose bengal as a photosensitizer and to compare the behavior of the polymer-bound dye to the behavior of the dye - free - in solution. In the present paper, therefore, we report on the photochemical and spectral properties of new singlet oxygen sensitizers based on soluble polystyrenes. These new derivatives are referred to as P -RB. 

We have shown38 that 8-methoxy-6-nitro-BIPS (11) is the only photochrome able to sensitize the formation of (h with a quantum yield A = 0.15 that is about one-fourth that of a commonly used singlet-oxygen sensitizer, i.e. methylene blue, for which 0A = 0.57.39 This benzopyran behaves as a good quencher of l02 as well. Unfortunately, in the paper by Guglielmetti and co-workers an analysis of the... 

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