Anthraquinone redox behavior

Redox behavior of anthraquinone is shown in Scheme 4. The quinone moiety may be reduced to the hydroquinone form and converted to a leuco salt under alkali conditions. In general, the leuco salt has a strong affinity for cellulose and is soluble in water. The hydroquinone form is insoluble in water and has low affinity to cellulose. The preferred dyeing procedure depends on the structure and properties of the vat dye. The variables that are used to control the process include, e.g., strength and amount of alkali, reduction temperature, and the presence of salts. During the process of reduction, some side reactions, such as overreduction, hydrolysis,... 

The anthraquinone exhibits a similar redox behavior as benzoquinone. Thus, redox luminescence switch can also be constructed with fluorophore linked to anthraquinone. For example, the luminescence of molecule 22, a ruthenium complex with an appended anthraquinone moiety, can be reversibly tuned through the interconversion between the anthraquinone and the corresponding hydroquinone.32... 

Abstract. The evolution of lariat ethers from relatively simple, substituted crown ethers into electrochem-ically sensitive ligands is presented. Although nitrogen-pivot lariats were observed to be better binders than the corresponding parent crowns and to retain considerable flexibility after complexation, overall stability constants were not favorable for cation transport applications. This led to the syntheses of nitrobenzene- and anthraquinone-substituted systems capable of reversible redox behavior and drastically enhanced cation binding abilities when reduced. Application of these in enhanced cation transport processes has been demonstrated. 

Yamamoto T, Etori H (1995) Poly(anthraquinone)s having a jc-cmain chain. Synthesis by organometallic polycondensation, redox behavior, and optical properties. Macromolecules 28 3371-3379... 

Newkome et al. have synthesized several dendrimers which contain a core of four diaminoanthraquinone molecules tethered together. Dendritic branches grow from these redox centers, and various isomers of the anthraquinones (AQs) have been examined. There were differences noted in the electrochemical behavior for the various isomers of diaminoanthraquinone, and, as might be expected, the electrochemical response of the redox centers became more irreversible as the dendrimer became larger [56]. 

DADMN adsorbed on a BPGE exhibits a symmetrical surface-redox wave in CV in the absence of oxygen in the pH range examined. Examples at pH 7.00 and 7.95 are depicted in Figures 1 and 2 as dotted lines. The reversible surface wave should be ascribed to a surface-redox reaction of the anthraquinone moiety of the adsorbed 7-DADMN. The behavior of these surface-redox waves can be interpreted in terms of a two-step one-electron surface-redox reaction (surface EE mechanism) . 

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