Diphenylisobenzofuran, reaction + singlet

Pyrene can sensitize the photooxidation of 1,3-diphenylisobenzofuran (72) in DTAC micellar solutions 61>. The reaction involves sensitization of singlet oxygen by pyrene which diffuses into another micelle and reacts with (72). Indole and tryptophan, which also react with singlet oxygen, quench the above reaction in ethanol solutions. However, in micellar systems they enhance the rate of reaction. Because of the high local concentrations of the quencher, the pyrene excited state is quenched by indole and tryptophan which leads to the photooxidation of (72) by a Type I process. 

Laser flash photolysis has been used to determine the bimolecular rate constants for the reaction between O2 ( A ) and several lipid-soluble and water-soluble substrates.1,3-diphenylisobenzofuran and 9,10-anthracene dipropionic acid disodium salt were used as singlet oxygen monitors. Prutz and Maier report on the time dependence of various fluorescence bands from O2 O2 ( 2 ) was... 

The dye-sensitized photo-oxidation of 1,3-diphenylisobenzofuran has been developed as a teaching experiment.286 1 The production of singlet oxygen by thiazine dye photosensitization as measured by the rate of photo-oxidation of tryptophan has been found to be very pH sensitive. The effect was shown to be related to the pJ5Ta s of the triplet dyes.2866 The occurrence of 2 in the photodynamic oxidations of guanosine,287 the reaction rates of bilirubin with 2 in the 874 877 878... 

Reactions of 1,3-diphenylisobenzofuran which is much more stable, are typical it undergoes Diels-Alder cycloaddition with diethyl acetylenedicarboxylate " and adds singlet oxygen, indeed this commercially available isobenzofuran is often used as a trapping reagent for transient alkenes and alkynes. Less stable isobenzofurans are traditionally generated and reacted in situ 1-methyl-3-phenylisobenzofuran is typical. More modern methods for the production of isobenzofurans in solution have allowed detailed study of the rates of various substituted derivatives with A-methylmaleimide. Diels-Alder additions are also known for benzo[c]thiophene and isoindoles. ... 

The spirolactone fluorescamine (432) reacts with primary amines to form highly fluroescent products making it a useful analytical reagent for the fluorometric determination of primary amines <72JA5927>. Diphenylisobenzofuran (433) continues to be useful as a trap for singlet oxygen and reactive alkenes. An example is its reaction with cyclopropabenzene (434), which is postulated to... 

Irradiation of a mixture of 1,3-diphenylisobenzofuran and cycloheptatriene gave four cross-cycloadducts some of the photochemical reactions may have been initiated by singlet exciplex formation between the reactants. " ... 

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