Carboxylic acids hydroxyl radical reactions with

It has been reported that formic acid is the most abundant carboxylic acid in the troposphere [127], In wet deposition, along with acetic acid, it accounts for up to 18% of the total acidity in rain in some areas [128]. The main chemical sink for atmospheric carboxylic acids is their reaction with the hydroxyl radical. 

Reaction pathway for carboxylic acids reacting with hydroxyl radical. 

Manevich Y, Held KD, Biaglow JE (1997) Coumarin-3-carboxylic acid as a detector for hydroxyl radicals generated chemically and by gamma radiation. Radiat Res 148 580-591 Maples KR, Johnson NF (1992) Fiber-induced hydroxyl radical formation correlation with mesothelioma induction on rats and humans. Carcinogenesis 13 2035-2039 MarkG, Korth H-G, Schuchmann H-P, von Sonntag C (1996) The photochemistry of aqueous nitrate revisited. J Photochem Photobiol A Chem 101 89-103 Maskos Z, Rush JD, Koppenol WH (1990) The hydroxylation of the salicylate anion by a Fenton reaction and v-radiolysis a consideration of the respective mechanisms. Free Rad Biol Med 8 153-162... 

Undecylenic acid has also been shown to react with the surface preferentially at the alkene end, leaving the terminal carboxylic acid group free for further reaction [53], This result was somewhat unexpected as the Si-H sites are considered to be somewhat acidic and the oxophilic nature of silicon should thermodynamically favor reaction with the hydroxyl group of the acid. The preferential reactivity with the alkenyl end is consistent with a free radical, rather than a nucleophilic mechanism. The acid function can be activated with N-hydroxy succinimide (NHS) to facilitate coupling with amine tagged molecules. Schematically,... 

Dagaut, P, Wallington, T.J., Liu, R., Kurylo, M.J. (1988) The gas-phase reactions of hydroxyl radicals with a series of carboxylic acids over the temperature range 240-440 K. Int J. Chem. Kinetics 20, 331-338. 

The combustion process is initiated by an ignition source converting some number of methane molecules into free radicals. Free radicals are in turn converted to OH free radical. Possible oxygenated compounds include aldehyde, alcohol, carboxylic acid, and oxide. The hydroxyl free radical then reacts with methane and is regenerated. The successive (chain type) combustion reaction is impeded by destruction of the OH radicals. Solid surfaces often destroy the OH radicals before they can react with hydrocarbons. The same effect is exploited in a porous-bed flame arrestor. In general, the combustion rates are very fast and nearly measurable with a few exceptional situations where time scales can be expanded to microseconds (KT6 s). The... 

The conversion of carboxylic acids into alcohols with one less carbon atom is an important synthetic transformation. Such decarboxylative hydroxylations have proven to be difficult to accomplish by classical ionic methods. Electrochemical decarboxylation (Hofer-Moest reaction) [23] has been applied successfully to different types of carboxylic acids such as amino acids (Scheme 11, Eq. 11.1) [24]. This reaction proceeds through an intermediate radical that is further oxidized to a car-benium ion and trapped by the solvent. The efficiency of the second oxidation step (the formation of the carbenium ion) depends on the ionization potential of the in-... 

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