Photochemistry and environment Part XIV. Phototransformation of nitrophenols induced by excitation of nitrite and nitrate ions

✍ Scribed by Admin Alif; Pierre Boule

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 635 KB
• Volume: 59
• Category: Article
• ISSN: 1010-6030
• DOI: 10.1016/1010-6030(91)87087-c

✦ Synopsis

The excitation of NOz-, HNOz or N09-in the presence of nitrophenol induces hydroxylations in the ortho or para positions with respect to the phenol function. No nitration is observed in contrast with phenol and hydroxybiphenyls. The reaction can be attributed to hydroxyl radicals formed in the photolysis of NOz-, HN02 and NO,-. With nitrite, the reaction is more efficient at 253.7 nm than at longer wavelengths. This effect is not, observed with HN02. When NO*-or HNOz are excited in the presence of nitrophenol, the formation of dihydroxynitrobenzenes competes with the scavenging of hydroxyl radicals by nitrite ions (or HNOJ and the efficiency of the reaction is significantly influenced by the relative concentrations.