Detailed Information on Publication Record
2007
Photochemically induced nitration and hydroxylation of organic aromatic compounds in the presence of nitrate or nitrite in ice.
MATYKIEWICZOVÁ, Nina, Romana KURKOVÁ, Jana KLÁNOVÁ and Petr KLÁNBasic information
Original name
Photochemically induced nitration and hydroxylation of organic aromatic compounds in the presence of nitrate or nitrite in ice.
Name in Czech
Fotochemicky indukovaná nitrace a hydroxylace aromatických organických sloučenin v přítomnosti dusičnanů a dusitanů v ledu.
Authors
MATYKIEWICZOVÁ, Nina (203 Czech Republic), Romana KURKOVÁ (203 Czech Republic), Jana KLÁNOVÁ (203 Czech Republic) and Petr KLÁN (203 Czech Republic, guarantor)
Edition
Journal of Photochemistry and Photobiology A: Chemistry, Amsterdam, The Netherlands, Elsevier Science, 2007, 1010-6030
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10401 Organic chemistry
Country of publisher
Netherlands
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 1.911
RIV identification code
RIV/00216224:14310/07:00020855
Organization unit
Faculty of Science
UT WoS
000244833600003
Keywords in English
Photochemistry; Ice; Snow; Nitrate; Nitrite; Aromatic compounds; Phenol; Nitration; Oxidation.
Tags
Tags
International impact, Reviewed
Změněno: 23/6/2009 15:13, prof. RNDr. Petr Klán, Ph.D.
V originále
The photochemistry of three model aromatic compounds (phenol, anisole, and 4 methoxyphenol; c = 0.001 mol/L) in frozen aqueous solutions containing sodium nitrite or nitrate (from c = 0.01 to 0.1 mol/L) at minus 15 C was investigated. Nitration, hydroxylation, and coupling reactions were found to be the principal chemical processes, presumably taking place in the quasi-liquid layer covering the ice crystal surfaces where both hydrophobic organic and water soluble inorganic compounds were accumulated prior to irradiation. While primary photoproducts were identified at low reaction conversions, exhaustive (quartz or Pyrex filtered) UV irradiation produced a very complex mixture of secondary photoproducts. The photoreactions proceeded predominantly by the nitrite or nitrate photoexcitation but chemistry of the excited organic chromophores was also observed. Phenol and 4 methoxyphenol photolysis afforded the corresponding nitro and hydroxycompounds, as well as biphenyl and diphenylether derivatives. The presence of nitrite or nitrate caused that qualitatively the same photoproducts were produced; therefore both were the source of the NOx or HO radicals. In contrast, irradiation of anisole under the same reaction conditions afforded phenol nearly exclusively. It is demonstrated that the OH group of phenols played an important role in the course of hydroxylation and nitration reactions. The results from this study may support assumptions according to which photolysis of nitrate in the snowpack is responsible for oxidation of organic precursors to their hydroxy or carbonyl derivatives.
In Czech
The photochemistry of three model aromatic compounds (phenol, anisole, and 4 methoxyphenol; c = 0.001 mol/L) in frozen aqueous solutions containing sodium nitrite or nitrate (from c = 0.01 to 0.1 mol/L) at minus 15 C was investigated. Nitration, hydroxylation, and coupling reactions were found to be the principal chemical processes, presumably taking place in the quasi-liquid layer covering the ice crystal surfaces where both hydrophobic organic and water soluble inorganic compounds were accumulated prior to irradiation. While primary photoproducts were identified at low reaction conversions, exhaustive (quartz or Pyrex filtered) UV irradiation produced a very complex mixture of secondary photoproducts. The photoreactions proceeded predominantly by the nitrite or nitrate photoexcitation but chemistry of the excited organic chromophores was also observed. Phenol and 4 methoxyphenol photolysis afforded the corresponding nitro and hydroxycompounds, as well as biphenyl and diphenylether derivatives. The presence of nitrite or nitrate caused that qualitatively the same photoproducts were produced; therefore both were the source of the NOx or HO radicals. In contrast, irradiation of anisole under the same reaction conditions afforded phenol nearly exclusively. It is demonstrated that the OH group of phenols played an important role in the course of hydroxylation and nitration reactions. The results from this study may support assumptions according to which photolysis of nitrate in the snowpack is responsible for oxidation of organic precursors to their hydroxy or carbonyl derivatives.
Links
| GA205/05/0819, research and development project |
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| MSM0021622412, plan (intention) |
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