Ferrocenesulfonic acids

Reaction with sulfuric acid or chlorosulfonic acid in acetic anhydride medium gives mono- and disuhstituted ferrocenesulfonic acid. 

Ferrocene can readily be sulfonated by either sulfuric acid or chlorosulfonic acid in acetic anhydride (43, 123). The products, ferrocenesulfonic acid (XXV) and ferrocene-l,l -disulfonic acid (XXVI), are obtained together with products resulting from oxidation. 

Li, X., Sun, C. and Zhou, F. (2006b), A novel nitrite sensor based on poly-l-naphthylamine doped by a ferrocenesulfonic-acid-modified electrode. J. Anal. Chem., 61(9) 896-901. 

Polyaniline nanowires with different sizes were synthesized by cychc voltammetry at different scan rates, in the presence of ferrocenesulfonic acid [24]. The scan potential was controlled at a range between -0.10 and +0.92 V (vs. SCE). Figure 17.2 shows SEM images of polyanUine films obtained by four cycles at scan rates of (a) 6, (b) 12, and (c) 30 mV s, and by six cycles at (d) 60 mVs . The SEM images in Figure 17.2 reveal the fact that all films are constructed of interwoven nanofibers with different diameters and... 

Y.F. Yang and S.L. Mu, Determination of hydrogen peroxide using amperometric sensor of polyaniline doped with ferrocenesulfonic acid. Biosens. Bioelectron., 21, lA-1% (2005). 

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