Reactions of peroxyacetyl nitrate

Leh, F., and J. B. Mudd. Reaction of peroxyacetyl nitrate with cysteine, qrstine. methionine, lipoic acid, papain, and lyso me. Arch. Biochem. Biophys. 161 216-221, 1974. 

Mudd, J. B. Reaction of peroxyacetyl nitrate with utathione. J. Biol. Chem. 241 4077-4080. 1966. 

Wendschuh, P. H., H. Fuhr, J. S. Gaffney, and I. N. Pitts, Jr. Reaction of peroxyacetyl nitrate with amines. Chem. Commun. 1973 74-75. 

Lee, Y. N., Kinetics of some aqueous-phase reactions of peroxyacetyl nitrate. Gas-Liquid Chemistry of Natural Waters," Vol. 1, BNL 51757, p. 21/1. Brookhaven Natl. Lab.,... 

C09-0114. In the lower atmosphere, NO2 participates in a series of reactions in air that is also contaminated with unbumed hydrocarbons. One product of these reactions is peroxyacetyl nitrate (PAN). The skeletal arrangement of the atoms in PAN appears at the right, (a) Complete the Lewis structure of this compound, (b) Determine the shape around each atom marked with an asterisk, (c) Give the approximate values of the bond angles indicated with arrows. 

Dugger, W. M., and I. P. Ting. The effect of peroxyacetyl nitrate on plants Photoreductive reactions and susceptibility of bean plants to PAN. Phytopathology 58 1102-1107, 1968. 

One product commonly formed in this reaction is peroxyacetyl nitrate (PAN), an important and common component of photochemical smog. PAN, ozone, and many of the other compounds formed in the series of reactions just described are strong oxidants and are responsible for some of the initial and most aggravating features of smog, including nose, eye, and throat irritation. 

As we have seen in Chapter 1, peroxyacetyl nitrate (PAN) is a powerful lachrymator and severe plant phytotoxicant formed in irradiated VOC-NOx mixtures from the reaction of peroxyacetyl radicals with N02 ... 

Stockwell, W.R., J.B. Milford, D. Gao and Y.J. Yang The effect of acetyl peroxy-peroxy radical reactions on peroxyacetyl nitrate and ozone concentrations, Atmos. Environ. 29 (1995) 1591-1599. 

Ozone can be formed also by a series of very complex reactions involving un-bumed hydrocarbons, aldehydes, nitrogen oxides, and oxygen. One of the products of these reactions is peroxyacetyl nitrate, PAN ... 

In the lower atmosphere that is also contaminated with unburned hydrocarbons, NO2 participates in a series of reactions. One product of these reactions is peroxyacetyl nitrate (PAN). The connectivity of the atoms in PAN appears below. 

An identical process is proposed for conversion of peroxyacetyl nitrate [20]. This reaction requires high mobility of the molecular fragments to build up six-membered complexes. In contrast to R O, the chain peroxide radicals in a rigid matrix of PTFE form such transition states with difficulty [21]. 

The UV absorption cross-sections of peroxyacetyl nitrate (PAN), CH3C(0)02N02, have been measured as a function of temperature (298, 273 and 250 K) between 195 and 345 nm. Photolysis becomes the most important atmospheric loss process for PAN, and the OH reaction is found to unimportant throughout the troposphere. 

The atmospheric lifetime of peroxyacetyl nitrate with respect to the removal by reaction with OH radicals is estimated to be more than 1 year. The wet and dry depositions are minor removal processes (Roberts, 1990). The thermal decomposition remains the most important loss process up to around 7 km, above which photolysis takes... 

Representation of Atmospheric Chemistry Through Chemical Mechanisms. A complete description of atmospheric chemistry within an air quaUty model would require tracking the kinetics of many hundreds of compounds through thousands of chemical reactions. Fortunately, in modeling the dynamics of reactive compounds such as peroxyacetyl nitrate [2278-22-0] (PAN), C2H2NO, O, and NO2, it is not necessary to foUow every compound. Instead, a compact representation of the atmospheric chemistry is used. Chemical mechanisms represent a compromise between an exhaustive description of the chemistry and computational tractabiUty. The level of chemical detail is balanced against computational time, which increases as the number of species and reactions increases. Instead of the hundreds of species present in the atmosphere, chemical mechanisms include on the order of 50 species and 100 reactions. 

Peroxyacetyl nitrate (PAN), H3CCO2ONO2, is a constituent of photochemical smog. It undergoes a first-order decomposition reaction with fi/2 = 32 min. 

Titanium dioxide suspended in an aqueous solution and irradiated with UV light X = 365 nm) converted benzene to carbon dioxide at a significant rate (Matthews, 1986). Irradiation of benzene in an aqueous solution yields mucondialdehyde. Photolysis of benzene vapor at 1849-2000 A yields ethylene, hydrogen, methane, ethane, toluene, and a polymer resembling cuprene. Other photolysis products reported under different conditions include fulvene, acetylene, substituted trienes (Howard, 1990), phenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2,6-dinitro-phenol, nitrobenzene, formic acid, and peroxyacetyl nitrate (Calvert and Pitts, 1966). Under atmospheric conditions, the gas-phase reaction with OH radicals and nitrogen oxides resulted in the formation of phenol and nitrobenzene (Atkinson, 1990). Schwarz and Wasik (1976) reported a fluorescence quantum yield of 5.3 x 10" for benzene in water. 

Photolytic. Synthetic air containing gaseous nitrous acid and exposed to artificial sunlight (A, = 300-450 nm) photooxidized 2-butanone into peroxyacetyl nitrate and methyl nitrate (Cox et al., 1980). They reported a rate constant of 2.6 x 10 cm /molecule-sec for the reaction of gaseous 2-butane with OH radicals based on a value of 8 x 10 cm /molecule-sec for the reaction of ethylene with OH radicals. 

The OH radical-initiated photooxidation of 2-butanone in a smog chamber produced peroxyacetyl nitrate and acetaldehyde (Cox et al., 1981). Reported rate constants for the reaction of 2-butanone with OH radicals in the atmosphere and in water are 1.15 x lO and 1.50 x 10 cmVmolecule-sec, respectively (Wallington and Kurylo, 1987 Wallington et al, 1988a). The rate constant for the reaction of 2-butanone and OH radicals in the atmosphere at 300 K is 2.0 x 10 cmVmolecule-sec (Hendry and Kenley, 1979). Cox et al. (1981) reported a photooxidation half-life of 2.3 d for the reaction of 2-butanone and OH radicals in the atmosphere. 

Major products reported from the photooxidation of o-xylene with nitrogen oxides include formaldehyde, acetaldehyde, peroxyacetyl nitrate, glyoxal, and methylglyoxal (Altshuller, 1983). The rate constant for the reaction of o-xylene and OH radicals at room temperature was 1.53 x 10 " cmVmolecule-sec (Hansen et al, 1975). A rate constant of 8.4 x 10 L/molecule-sec was reported for the reaction of o-xylene with OH radicals in the gas phase (Darnall et al., 1976). Similarly, a room temperature rate constant of 1.34 x 10 " cmVmolecule-sec was reported for the vapor-phase reaction of o-xylene with OH radicals (Atkinson, 1985). At 25 °C, a rate constant of 1.25 X 10 " cmVmolecule-sec was reported for the same reaction (Ohta and Ohyama, 1985). 

Another important phytotoxic atmospheric pollutant that has been studied with respect to its inhibitory effects on plant photosynthesis is peroxyacetyl nitrate (PAN). This phytotoxicant applied for 30 min at 1 ppm depressed the incorporation of 1 C02 into intact pinto bean leaves, but only after visible tissue injury started to develop (20). From companion studies on isolated chloroplasts, it was concluded that PAN-induced inhibition was probably associated with the carboxylating reaction or the chloroplast light-energy conversion system leading to assimilative power. The inhibition appeared to result in a quantitative reduction (but not a qualitative change) in the early products of photosynthesis. 

Seefeld, S D. J. Kinnison, and J. Alistair Kerr, Relative Rate Study of the Reactions of Acetylperoxy Radicals with NO and N02 Peroxyacetyl Nitrate Formation under Laboratory Conditions Related to the Troposphere, J. Phys. Chem. A, 101, 55-59 (1997). 

Nitrogen Oxide Reactions. Examination of possible aqueous-phase reactions of nitrogen dioxide and peroxyacetyl nitrate has revealed no reactions of importance to cloud chemistry (21,22). This situation is a consequence of the low solubilities and/or low reactivities of these gases with substances expected to be present in cloudwater, although studies with actual precipitation samples would be valuable in confirming this supposition. NO2 has been shown (23) to react with dissolved S(IV), but the details of the mechanism and rate of this reaction remain to be elucidated. 

Step 3. The conversion of NO emissions from cars to N02 by the reactions of CO and hydrocarbons increases the concentration of ozone during the day. N02 and hydrocarbons react to give aldehydes (e.g., acetaldehyde, CH3CHO), ozone, and peroxyacetyl nitrate (PAN). A typical hydrocarbon is ethane (CH3CH3). Thus,... 

---