Photochemically triggered oxidation

It was suggested that in the photochemically triggered oxidation of phenol by Ru(bpy)3, the proton charge was delocalized over a primary shell of water molecules firmly bound to the pyridinium cation.The tetra-2-oxypyridinate ruthenium(II, III) dimer [Ru2(hp)4Cl] and related diruthenium adducts were effective catalyst for the oxidation of allylic and benzylic C—H bonds. The bis(homoallylic) sulfamate esters were converted to the corresponding allylic amines using PhI(02C Bu)2 in CH2CI2. Both computational and experimental studies favoured a stepwise mechanism involving H atom abstraction/radical recombination and the intermediacy of a discrete short-lived diradical species. ... 

The Search for Other Potential CORMs The very intense and fruitful research effort supported by the experimental CORMs attracted other research groups to the field and new molecules emerged. These new CORMs can be divided according to the type of trigger that initiates CO release chemical reactions (substitution, pH changes, oxidation), photochemical reactions, and enzymatic reactions. 

The preceding sections dealt with thermal heterogeneous and homogeneous reductive and oxidative cleavages. These reactions may also be triggered photochemically by means of a sentitizer as pictured in Scheme 3.7 in the... 

In this contribution the re-evaluated yields from the OH-radical initiated oxidation of benzene, toluene, p-xylene, and initial results of new simulation chamber experiments on prompt glyoxal formation from isoprene oxidation are presented. A detailed discussion of sources, sinks and their uncertainties to model atmospheric concentrations of glyoxal is presented, and exemplifies how basic research in environmental simulation chambers besides giving input for photochemical models also triggers advancements with measurement techniques for field observations. The integration of laboratory and field observations by models in turn will guide future research on atmospheric chemical processes. 

Although we wish to preserve the ozone in the stratosphere, we want to minimize its production in the troposphere, that part of the atmosphere where we live. Photochemical smog produced as a result of the action of solar radiation on the effluents from automobiles is the primary source of ozone in the troposphere. The trigger for photochemical smog is based on nitrogen oxide chemistry, so we defer our discussion of this problem until Chapter 16 on Group 5A chemistry. 

The vitamin is important in animal growth, reproduction, the maintenance of function of mucous membranes and vision, but only in the latter case can its role be adequately defined at the molecular level. The enzymic oxidation product of retinol, ll-cis-retinal (Figure 5.6) complexes with a protein, opsin, in the retinal rods to form the conjugated protein, rhodopsin. The visual process consists of a series of reactions triggered by the photochemical isomerization of 11-cw-retinal to all-traw5-retinal. 

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