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8328918 
Journal Article 
Diazonium salts in photochemistry V: photosensitized decomposition of benzenediazonium tetrafluoroborate in solutions of cationic detergents 
Scaiano, JC; Kim-Thuan, N; Leigh, WJ 
1984 
0 
Journal of Photochemistry
ISSN: 0047-2670
EISSN: 1873-2658 
24 
1 
79-86 
English 
The photodecomposition of benzenediazonium tetrafluoroborate in solutions of cationic micelles was examined. While both direct and triplet-sensitized (employing a predominantly micelle-bound sensitizer) photolysis results in the formation of phenyl cations, the product mixtures indicate that the intermediate is formed, and subsequently reacts, in different micro-environments in the two cases. Thus phenol is formed as the almost exclusive product upon direct photolysis of the diazonium salt in dodecyltrimethyl-ammonium bromide micellar solution, while phenanthrene-sensitized photolysis yields bromobenzene as the major product together with phenol and benzene. The formation of benzene is believed to result from short-chain processes involving phenyl radicals, perhaps formed by competing electron transfer by the sensitizer. This is substantiated by using anthracene, which is a good electron donor, as the sensitizer; this leads to the predominant formation of benzene. The addition of relatively large amounts of chloride ion to the mixtures does not affect significantly the product ratios, illustrating the known higher binding constant of bromide to cationic micelles. © 1984.