O-Aminobenzenesulfonic acid

Fig. 23 ESR spectra of Cu2Cr/aniline sulfonic acid derivatives after a thermal treatment at 200 °C for 4h in air recorded at 105 K with a sweep width of a 6500 G b 150 G. H(I) o-aminobenzenesulfonic acid H(I) m-aminobenzenesulfonic acid H(III) ...

The influence of the sulfonic acid group upon the course of ethanol deaminations somewhat resembles that of the methyl group. Thus, o-aminobenzenesulfonic acid gives only the ether 18 the meta isomer yields a mixture of m-ethoxybenzenesulfonic acid and benzenesulfonic acid (the ether predominates) 18> 19 and from p-aminobenzenesulfonic acid the only product isolated is benzenesulfonic acid.20... 

Remarks. Ferrous sulfate can be used advantageously instead of salt to precipitate the m-nitrobenzenesulfonic acid. The iron salt is very difficultly soluble in 20 per cent sulfuric acid and can be filtered off directly without further treatment. The reduction is carried out exactly as described above. If benzene is sulfonated with 100 per cent sulfuric acid, and then the benzenesulfonic acid is nitrated at 100°, there are formed, according to the work of Obermiller, besides the meta sulfonic acid, considerable quantities of the ortho and para isomers. The latter can be separated quite easily tluough the magnesium salts, and this affords a method for obtaining the valuable o-aminobenzenesulfonic acid. The preparation of orthanilic acid starting with o-m trochlorobenzene has also been described. ... 

C. Barbero, R. Koetz, Electrochemical formation of a self-doped conductive polymer in the absence of a supporting electrolyte. The copolymerization of o-aminobenzenesulfonic acid and aniline, Advanced Materials 1994, 6, 577. 

Figure 2.43 SEM images of self-doped poly(o-aminobenzenesulfonic acid-coaniline) microflowers at (A) low and (B) high magnifications. (Reprinted from Electrochemistry Communications, 7, Z. Wang, L. Jiao, T. You, L. Niu, S. Dongs, A. Ivaska, 875. Copyright (2005), with permission from Elsevier.)...

Self-doped polyaniline nanofibers have been synthesized recently by Yang et al. [249] via a self-assembly process using the self-doped monomer (o-aminobenzenesulfonic acid) and aniline. It was suggested that the sulfonated monomer (o-aminobenzenesulfonic acid) plays a dual role as a monomer and a surfactant in the nanofiber formation. The nanofibers were synthesized chemically using different molar ratios of aniline/o-aminobenzenesulfonic acid without an external dopant. It was proposed that the o-aminobenzenesulfonic acid and anilinium cations form micelles in aqueous solution, which further act as templates to form nanofibers. Self-doped polyaniline nanofibers with an average diameter of 370 nm synthesized using an aniline/o-aminobenzenesulfonic acid... 

Figure 2.44 SEM image of self-doped polyaniline nanofibers synthesized using an aniline/o-aminobenzenesulfonic acid mole ratio of 1. (Reprinted from Polymer, 46, C. H. Yang, Y. K. Chib, H. E. Cheng, C. H. Chen, 10688. Copyright (2005), with permission from Elsevier.)...

Fully sulfonated polyaniline nanoparticles, nanofibers and nanonetworks have been obtained by electrochemical homopolymerization of o-aminobenzenesulfonic acid for the purpose of mediating the electrochemistry of cyctochrome c [252]. The nanostructures were synthesized in a mixed solvent of acetonitrile and water (8 1) at 0°C by following a three-step galvanostatic procedure. First, a relatively high current density is applied to initiate the polymerization. This is followed by two periods during which lower current densities are applied. 

A typical procedure involves 0.06mA-cm for 0.5 h, followed by 0.03mA-cm for 3h, which was then followed by another 3 b at 0.015 mA -cm Poly(o-aminobenzenesulfonic acid) nanoparticles of... 

J. H. Fan, M. X. Wan, D. B. Zhu, Synthesis and characterization of water-soluble conducting copolymer poly(aniline-co-o-aminobenzenesulfonic acid), Journal of Polymer Science Part A - Polymer Chemistry 1998, 36, 3013. 

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