Yield singlet oxygen

The endoperoxides of polynuclear aromatic compounds are crystalline soHds that extmde singlet oxygen when heated, thus forming the patent aromatic hydrocarbon (44,66,80,81). Thus 9,10-diphenyl-9,10-epidioxyanthrancene [15257-17-7] yields singlet oxygen and 9,10-diphenylanthracene. 

Further reaction of HOCl with HjOj can yield singlet oxygen ... 

A number of photophysical studies have been reported concerning the interactions of ground state amines with dyes. Foote (28) first suggested that dye triplets could interact with oxygen to yield singlet oxygen. Similar interaction of dye triplets with aromatic amines can lead to dye quenching via electron transfer (29-31). 

The final steps in the overall sequence were then carried out as demonstrated in Scheme 22. Coupling of the enol triflate with dimethylcopper lithium provided the diene 244 in excellent yield. Singlet oxygenation of244 was then investigated with a variety of dyes in different solvents. We were surprised to find that a mixture of diastereomeric peroxides were obtained, only varying slightly with conditions, and... 

The exact nature of the brominating species released by the enzyme is unknown. Hypobromous acid is known (35) to be in rapid equilibrium with molecular bromine and tribromide ions in aqueous solutions. Further, it is important to note that at neutral pH values a very fast reaction occurs between H2O2 and OBr to yield singlet oxygen (36). This rapid side reaction hampers direct observation of brominating species at neutral pH values and is why rapid-reaction kinetics had to be used by De Boer and Wever (33) to detect Bri formation. 

Wefers, H., and Stes, H. (1983). Oxidation of glutathione by the superoxide radical to the distilfide and the sulfonate yielding singlet oxygen. Eirr. /. Biackem. 137, 29-36. 

It has also been found that the alkaline hydrolysis of peroxyacetyl nitrate (CH3 C002 N02) yields singlet oxygen 102 (1 Ag) [ 587]. 

Electron transfer reactions Of biological interest, the enzyme myeloperoxidase, present in neutrophiles, can catalyze the formation of hypochlorite from Cf and H Oj The further reaction of hydrogen peroxide (H O ) with formed HOCl yields singlet oxygen ( o ) ... 

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