Organic redox reactions

Carbonates are widely used as buffers in organic redox reactions, and the formation of COj should be taken into account in interpretation of their mechanisms. There are promising reports on CO3 as a potential oxidant for the environmental-friendly delignification of pulp (Stenman et al. 2003, Carlsson et al. 2006). 

The photoelectrochemical reduction of the N = N double bond of the diaryl azo dye methyl orange can be similarly sensitized by colloidal titanium dioxide les, isoj The reaction was sensitive to pH and the identity of the organic redox reaction could be shifted by conducting the photoreaction in the presence of surfactants. Cationic surfactants increased the efficiency of oxidative cleavage by inhibiting charge recombination. Polyvinyl alcohol instead favored reduction. The ambident photoactivity of methyl orange thus makes it an attractive probe for activity of irradiated semiconductor suspensions. 

When dealing with transformation reactions, it is important to know whether electrons have been transferred between the reactants. For evaluating the number of electrons transferred, it is convenient to examine the (formal) oxidation states of all atoms involved in the reaction. Of particular interest to us will be the oxidation state of carbon, nitrogen, and sulfur in a given organic molecule, since these are the elements most frequently involved in organic redox reactions. 

Figure 9-1. A number of organic redox reactions, showing the formal oxidation state of the carbon in each of the compounds.

These rules, however, are not easily applied to organic redox reactions, and this difficulty has led to a steady stream of alternative methods for assigning oxidation states (e.g., 6, 7). 

Control of Solution Acidity. Many inorganic and organic redox reactions involve hydronium ions, for example... 

Standard electrode potentials and other free energy data for organic redox reactions 122... 

List of different types of organic redox reactions, emphasizing their synthetic scope... 

For all reactions (2) with at least one component uncharged, AG = 0 if, as is normally done, we exclude dipole-dipole interactions. This means that AGf can be neglected for many organic electron-transfer reactions. Otherwise, in media that are often used for organic redox reactions the electrostatic effects are formally fairly large and certainly not negligible. The effect of cations upon the disproportionation of radical anions (41) in ethereal media is an example of... 

STANDARD ELECTRODE POTENTIALS AND OTHER FREE ENERGY DATA FOR ORGANIC REDOX REACTIONS... 

The experimental fundamentals for differentiating between metal and porphyrin ring reactions have been given in Section III, thus only the products of the organic redox reactions will be discussed in the following paragraphs. 

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