title: On the effect of pH in aromatic photonitration upon nitrate photolysis.
abstract: This paper studies the pH effect on the photonitration of catechol, 1-naphthol, naphthalene, and benzene. The pH trend is influenced by the generation of HNO(2) and peroxynitrous acid (HOONO) upon nitrate photolysis. HNO(2) can be involved in a direct and an indirect nitration process. Direct nitration follows the pH distribution of HNO(2) (flexus around 3). Indirect nitration, possibly involving nitrosation+oxidation, would be highest around pH3. HOONO can be involved in electrophilic nitration, where the initial formation rate of the nitroderivatives is proportional to [H(+)], or take part in nitration directly, in which case a less important pH effect in photonitration is observed. The relative importance of the various nitration pathways for each substrate determines the resulting pH effect in photonitration upon nitrate photolysis.
authors.affiliation: Dipartimento di Chimica Analitica, Università di Torino, Via P. Giuria 5, 10125 Torino, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Minero
authors.forename: Francesca
authors.initials: F
authors.lastname: Bono
authors.forename: Francesca
authors.initials: F
authors.lastname: Rubertelli
authors.forename: Davide
authors.initials: D
authors.lastname: Pavino
authors.forename: Valter
authors.initials: V
authors.lastname: Maurino
authors.forename: Ezio
authors.initials: E
authors.lastname: Pelizzetti
authors.forename: Davide
authors.initials: D
authors.lastname: Vione
mesh_terms: D001554:Benzene / Q000494:pharmacology*; D002396:Catechols / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007259:Infrared Rays; D009281:Naphthalenes / Q000494:pharmacology*; D009284:Naphthols / Q000494:pharmacology*; D009566:Nitrates / Q000737:chemistry*; D010782:Photolysis / Q000187:drug effects*
chemical_list: D002396:Catechols; D009281:Naphthalenes; D009284:Naphthols; D009566:Nitrates; C031721:naphthalene; C029350:1-naphthol; D001554:Benzene; C034221:catechol