Hydroxyl radical reactions

Atrazine is successively transformed to 2,4,6-trihydroxy-l,3,5-triazine (Pelizzetti et al. 1990) by dealkylation of the alkylamine side chains and hydrolytic displacement of the ring chlorine and amino groups (Figure 1.3). A comparison has been made between direct photolysis and nitrate-mediated hydroxyl radical reactions (Torrents et al. 1997) the rates of the latter were much greater under the conditions of this experiment, and the major difference in the products was the absence of ring hydroxylation with loss of chloride. 

Brubaker WW, RA Hites (1997) Polychlorinated dibenzo-/)-dioxins and dibenzofurans gas-phase hydroxyl radical reactions and related atmospheric removal. Environ Sci Technol 31 1805-1810. 

Photolysis of O3 yields O2 and electronically excited 0( D), which can either be collisionally stabilized (reaction 6.18) or react with a water molecule to yield two hydroxyl radicals (reaction 6.19). Atmospheric concentrations of hydroxyl radical on a 24-h seasonal average basis are estimated at 1 X 10 molecules cm while peak daytime concentrations of 46 X 10 molecules cm have been observed. ... 

Gusten, H., Filby, W.G. and Schoaf, S., Prediction of Hydroxyl Radical Reaction Rates with Organic Compounds in the Gas Phase, Atmospheric Environ., 15 1763-1765 (1981). 

Atkinson R, Carter WPL, Aschmann SM, et al. 1985. Atmospheric fates of organic chemicals Prediction of ozone and hydroxyl radical reaction rates and mechanisms. Research Triangle Park, NC U.S. Environmental Protection Agency, Office of Research and Development. 

Guesten, H., Filby, W.G., Schoop, S. (1981) Prediction of hydroxyl radical reaction rates with organic compounds in the gas phase. Atmos. Environ. 15, 1763-1765. 

Kwok, W.S.C., Atkinson, R. (1995) Estimation of hydroxyl radical reaction rate constants for gas-phase organic compounds using a structure reactivity relationship an update. Atmos. Environ. 29, 1685-1695. 

The aromatic-hydroxyl radical reaction has been studied by Davis et They reported rate constants for benzene and toluene and concluded that hydroxyl additions to the aromatic ring compete favorably with the abstraction of hydrogen atom from the alkyl substituent. Doyle et al recently published hydroxyl reaction rate constants for a series of alkylbenzenes. 

FIGURE 3 12 Possible initial steps for ozone, atomic oxygen, nitrogen dioxide, and hydroxyl-radical reaction with aromatic hydrocarbons. 

FIGURE 3-13 Relations between conversion of nitric oxide to nitrogen dioxide and ozone, atomic oxygen, and hydroxyl-radical reaction rate constants. Reprinted with permission from Grosjean. ... 

Good, D.A., Hanson,]., Francisco, ].S., Li, Z., andjeong, G.-R. Kinetics and reaction mechanism of hydroxyl radical reaction with methyl formate, J. Phys. Chem. A, 103(50) 10893-10898, 1999. 

Kenley, R.A., Davenport, J.E., and Hendry, D.G. Hydroxyl radical reactions in the gas phase. Products and pathways for the... 

Hodson J. 1988. The estimation of the photodegradation of organic compoundsby hydroxyl radical reaction rate constants obtained from nuclear magneticresonance spectroscopy chemical shift data. Chemosphere 17 2339- 2348. 

Although the radiation-induced oxidation of ethanol has been fully in-- vestigated (2, 22, 23), little work has been published on the oxidation of other alcohols. In connection with a project concerned with the relative rates of hydroxyl radical reactions using 2-propanol as reference solute, it was thought desirable first to investigate the radiation chemistry of 2-propanol-oxygen solutions both in aqueous solution and pure 2-propa-nol. The results of this investigation are presented here. 

Baxley, J. S M. V. Henley, and J. R. Wells, The Hydroxyl Radical Reaction Rate Constant and Products of Ethyl 3-Ethoxypropionate, hit. J. Chem. Kinet., 29, 637-644 (1997). 

Hodson, J., The Estimation of the Photodegradation of Organic Compounds by Hydroxyl Radical Reaction Rate Constants Obtained from Nuclear Magnetic Resonance Spectroscopy Chemical Shift Data, Chemosphere, 17, 2339-2348 (1988). 

Kwok, E. S. C., and R. Atkinson, Estimation of Hydroxyl Radical Reaction Rate Constants for Gas-Phase Organic Compounds Using a Structure-Reactivity Relationship An Update, Atmos. Enriron., 29, 1685-1695 (1995). 

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