Organic hydroxyl radical

The one-step synthesis of a,co-hydroxylated dimers of 1,3-dienes or maleic acid uses alcohol (t-butanol, n-butanol, isopropanol, ethanol)/H202/FeS04 as a catalyst 72 73>. Organic hydroxylated radicals are generated from the alcohol by hydrogen abstraction ... 

In the atmosphere, there are three reactants that determine the rate of degradation of organics hydroxyl radicals, ozone, and nitrate radicals. The hydroxyl radical is by far the most important, since it reacts with most organics, with the exception of fully halogenated compounds (no hydrogen to abstract). Ozone is important for only a small group of compoimds, i.e., acetylenics and olefins. Nitrate radicals are only important at night and only react rapidly with a few classes of chemicals (e.g., phenols, mercaptans). 

Hydroxyl radicals damage the mitochondrial (chromoplastic), microsomal (peroxysomal) and endoplasmic reticulum membranes. The damage associated with many degenerative processes (diseases) includes certain forms of cancer and occurs even during the normal aging of organisms. Hydroxyl radicals operate mainly at the place of formation, where they attack unsaturated fatty acid (RH) bound in the membrane phospholipids. Unsaturated fatty... 

The hydroxyl radical is responsible for some of the oxidation products of organic compounds by peroxonitrous acid. 

Atkinson R. 1985. Kinetics and mechanisms of the gas-phase reactions of hydroxyl radical with organic compounds under atmospheric conditions. Chem Rev 85 69-201. 

The transformation of arenes in the troposphere has been discussed in detail (Arey 1998). Their destruction can be mediated by reaction with hydroxyl radicals, and from naphthalene a wide range of compounds is produced, including 1- and 2-naphthols, 2-formylcinnamaldehyde, phthalic anhydride, and with less certainty 1,4-naphthoquinone and 2,3-epoxynaphthoquinone. Both 1- and 2-nitronaphthalene were formed through the intervention of NO2 (Bunce et al. 1997). Attention has also been directed to the composition of secondary organic aerosols from the photooxidation of monocyclic aromatic hydrocarbons in the presence of NO (Eorstner et al. 1997) the main products from a range of alkylated aromatics were 2,5-furandione and the 3-methyl and 3-ethyl congeners. 

Torrents A, BG Anderson, S Bilboulian, WE Johnson, CJ Hapeman (1997) Atrazine photolysis mechanistic investigations of direct and nitrate-mediated hydroxyl radical processes and the influence of dissolved organic carbon from the Chesapeake Bay. Environ Sci Technol 31 1476-1482. 

Anbar, M. and Neta, P. (1967). A compilation of specific biomolecular rate constants for the reaction of hydrated electrons, hydrogen atoms and hydroxyl radicals with inorganic and organic compounds in aqueous solutions. Int. J. Appl. Radiat. Isot. 18, 493-497. 

A few interesting organic molecules may possess the ability to release hydroxyl radical under physiological conditions. The most extensively studied of these is 3-amino-l,2,4-benzotriazine 1,4-dioxide (tirapazamine, 95, Scheme 8.32). Tirapazamine is a bioreductively activated DNA-damaging agent that selectively kills the oxygen-poor (hypoxic) cells found in solid tumors. The biological activity of... 

The use of ultrasound in both the synthesis and crystallisation of a broad array of both organic and inorganic materials has been intensively researched and is well documented [61-64]. An application of ultrasound that has received relatively less attention however, is in the dissolution of colloidal particles. Prakash and Ghosh [65] reported on the dissolution of silver colloids under 1 MHz ultrasound irradiation, proposing that the silver is oxidised by sonochemically produced hydroxyl radicals. Sostaric et al. [66] investigated the dissolution of MnC>2 colloids in the presence of aliphatic alcohols at a lower frequency of 20 kHz. They found that... 

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). 

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