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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.47A [2008] >
IJC-A Vol.47A(09) [September 2008] >
| Title: | Micellar effects on dye sensitized photooxidation of phenothiazine |
| Authors: | Kathuria, Shipra Gupta, P K Dhamiwal, N R |
| Issue Date: | Sep-2008 |
| Publisher: | CSIR |
| Abstract: | Methylene blue sensitized photooxidation of phenothiazine (PTH) in sodium dodecylsulphate, cetyl trimethylammonium bromide and brij-35 in methanol-water, ethanol-water and acetonitrile-water gives phenothiazine-3-one (PTN) and phenothiazine sulphoxide as the products at low conversion. A small shift in the λmax indicates the formation of an additional product, which is destroyed during the separation. An inverse relationship between log Φ (Φ= quantum yield of PTN formation) and 1/Є₀ (Є₀ = dielectric constant of the medium) supports the participation of singlet oxygen (¹O₂) at low [PTH]. A mechanism consistent with the results showing the participation of ¹O₂ at low [PTH] and electron transfer-exciplex formation at high [PTH] is postulated. The formation of phenothiazine sulphoxide has been suggested to be through the phenothiazinyl radical. |
| Page(s): | 1384-1388 |
| ISSN: | 0376-4710 |
| Source: | IJC-A Vol.47A(09) [September 2008]
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