The Full Wiki

Fuchsine: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.


From Wikipedia, the free encyclopedia

CAS number 632-99-5 Yes check.svgY
RTECS number 8053-09-6
Molecular formula C20H20N3·HCl
Molar mass 337.86 g/mol (hydrochloride)
Melting point


Solubility in water 2650 mg/L (25°C)
log P 2.920
Vapor pressure 7.49E-10 mm Hg (25°C)
kH 2.28E-15 atm-m3/mole (25°C)
Atmospheric OH rate constant 4.75E-10 cm3/molecule-sec (25°C)
Main hazards Ingestion, inhalation, skin and eye contact, combustible at high temperature, slightly explosive around open flames and sparks.
NFPA 704
NFPA 704.svg
 Yes check.svgY (what is this?)  (verify)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Fuchsine or rosaniline hydrochloride is a magenta dye with chemical formula C20H19N3·HCl.[1][2] There are other similar chemical formulations of products sold as fuchsine, and several dozen other synonyms of this molecule.[1]

It becomes magenta when dissolved in water; as a solid, it forms dark green crystals. As well as dying textiles, fuchsine is used to stain bacteria and sometimes as a disinfectant. In the literature of biological stains the name of this dye is frequently mis-spelled, with omission of the terminal e, which indicates an amine[3] American and English dictionaries (Webster's, Oxford, Chambers etc) give the correct spelling, which is also used in the literature of industrial dyeing[4].



Fuchsine, named by its original manufacturer Renard frères et Franc,[5] is usually cited with one of two etymologies: from the color of the flowers of the plant genus Fuchsia,[6] named in honor of botanist Leonhart Fuchs, or as the German translation Fuchs of the French name Renard, which means fox.[7] An 1861 article in Répertoire de Pharmacie said that the name was chosen for both reasons.[8]

Acid fuchsine

Acid fuchsine is a mixture of homologues of basic fuchsin, modified by addition of sulfonic groups. While this yields twelve possible isomers, all of them are satisfactory despite slight differences in their properties.

Basic fuchsine

Basic fuchsine is a mixture of rosaniline, pararosaniline, new fuchsine and Magenta II [9]. Formulations usable for making of Schiff reagent must have high content of pararosanilin. The actual composition of basic fuchsine tends to somewhat vary by vendor and batch, making the batches differently suitable for different purposes.

In solution with phenol as an accentuator it is called carbol fuchsin and is used for the staining of the bacterium which causes tuberculosis.[10]

See also


  1. ^ a b "Basic chemical data". Discovery Series online database, Developmental Therapeutics Program, U.S. National Institutes of Health. Retrieved on 2007-10-08.
  2. ^ Goyal, S.K. "Use of rosaniline hydrochloride dye for atmospheric SO2 determination and method sensitivity analysis". Journal of Environmental Monitoring, 3, 666-670, DOI: 10.1039/b106209n. Retrieved on 2007-10-08.
  3. ^ Baker JR (1958) Principles of Biological Microtechnique. London: Methuen.
  4. ^ Hunger K (2003) Industrial Dyes. Chemistry, Properties, Applications. Weinheim: wiley-VHC.
  5. ^ Béchamp, M. A. (January-June 1860.) "Comptes rendus hebdomadaires des séances de l'Académie des sciences. 1860. (T. 50)." French Academy of Sciences, Mallet-Bachelier: Paris, tome 50, page 861. Retrieved on 2007-09-25.
  6. ^ (2004.) "Fuchsin" The American Heritage Dictionary of the English Language, Fourth Edition, Houghton Mifflin Company, via Retrieved on 2007-09-20
  7. ^ "Fuchsine." (Website.) ARTFL Project: 1913 Webster's Revised Unabridged Dictionary. Retrieved on 2007-09-25
  8. ^ Chevreul, M. E. (July 1860). "Note sur les étoffes de soie teintes avec la fuchsine, et réflexions sur le commerce des étoffes de couleur." Répertoire de Pharmacie, tome XVII, p. 62. Retrieved on 2007-09-25.
  9. ^ Horobin RW & Kiernan JA 20002. Conn's Biological Stains, 10th ed. Oxford: BIOS, p.184-191
  10. ^ Clark G 1973 Staining Procedures Used by the Biological Stain Commission, 3rd ed. Baltimore: Williams & Wilkins, pp. 252-254

1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

FUCHSINE, or Magenta, a red dyestuff consisting of a mixture of the hydrochlorides or acetates of pararosaniline and rosaniline. It was obtained in 1856 by J. Natanson (Ann., 1856, 9 8, p. 297) by the action of ethylene chloride on aniline, and by A. W. Hofmann in 1858 from aniline and carbon tetrachloride. It is prepared by oxidizing "aniline for red" (a mixture of aniline and orthoand para-toluidine) with arsenic acid (H. Medlock, Dingler's Poly. Jour., 1860, 158, p. 146); by heating aniline for red with nitrobenzene, concentrated hydrochloric acid and iron (Coupier, Ber., 1873, 6, p. 423); or by condensing formaldehyde with aniline and ortho-toluidine and oxidizing the mixture. It forms small crystals, showing a brilliant green reflex, and is soluble in water and alcohol with formation of a deep red solution. It dyes silk, wool and leather direct, and cotton after mordanting with tannin and tartar emetic (see Dyeing). An aqueous solu tion of fuchsine is decolorized on the addition of sulphurous acid, the easily soluble fuchsine sulphurous acid being formed. This solution is frequently used as a test reagent for the detection of aldehydes, giving, in most cases, a red coloration on the addition of a small quantity of the aldehyde.

The constitution of the fuchsine bases (pararosaniline and rosaniline) was determined by E. and 0. Fischer in 1878 (Ann., 1878, 194, p. 242); A. W. Hofmann having previously shown that oxidation of pure aniline alone or of pure toluidine yielded no fuchsine, whilst oxidation of a mixture of aniline and para-toluidine gave rise to the fine red dyestuff para-fuchsine (pararosaniline hydrochloride) CH 3 C 6 H 4 NH 2 +2C 6 H 5 NH 2 +30 = HOC(C 6 H 4 NH 2) 3 +2H20.

Colour base (pararosaniline).

HO C(C 6 H 4 NH 2) 3 HC1=H 2 0+(H 2 N C 6 H 4) 2 C: C 6 H 4: NH2C1.

Pararosaniline hydrochloride.

A. Rosenstiehl (Jahres., 1869, p. 693) found also that different rosanilines were obtained according to whether orthoor para-toluidine was oxidized with aniline; and he gave the name rosaniline to the one obtained from aniline and ortho-toluidine, reserving the term pararosaniline for the other. E. and 0. Fischer showed that these compounds were derivatives of triphenylmethane and tolyldiphenylmethane respectively. Pararosaniline was reduced to the corresponding leuco compound (paraleucaniline), from which by diazotization and boiling with alcohol, the parent hydrocarbon was obtained (H 2 N C 5 H 4) 2 C:C 6 H 4 :NH 2 Cl - HC(C6H4NH2 HCl)3 - >HC(C6H4N2C13) Pararosaniline hydrochloride. Paraleucaniline.

-> HC(C6H5) 3.


The reverse series of operations was also carried out by the Fischers, triphenylmethane being nitrated, and the nitro compound then reduced to triaminotriphenylmethane or paraleucaniline, which on careful oxidation is converted into the dyestuff. A similar series of reactions was carried out with rosaniline, which was shown to be the corresponding derivative of tolyldiphenylmethane.

The free pararosaniline, C19H19N30, and rosaniline, C20H21N30, may be obtained by precipitating solutions of their salts with a caustic alkali, colourless precipitates being obtained, which crystallize from hot water in the form of needles or plates. The position of the amino groups in pararosaniline was determined by the work of H. Caro and C. Graebe (Ber., 1878, I I, p. 1348) and of E. and 0. Fischer (Ber., 1880, 13, p. 2204) as follows: Nitrous acid converts pararosaniline into aurin, which when superheated with water yields para-dioxybenzophenone. As the hydroxyl groups in aurin correspond to the amino groups in pararosaniline, two of these in the latter compound must be in the para position. The third is also in the para position; for if benzaldehyde be condensed with aniline, condensation occurs in the para position, for the compound formed may be converted into para-dioxybenzophenone, C6H5CHO -)C6H5CH(C6H4NH2)2 - >C6H5CH(C6H40H)2 -->CO(C6H40H)2 but if para-nitrobenzaldehyde be used in the above reaction and the resulting nitro compound N02 C6H4 CH(C6H4NH2)2 be reduced, then pararosaniline is the final product, and consequently the third amino group occupies the para position. Many derivatives of pararosaniline and rosaniline are known, in which the hydrogen atoms of the amino groups are replaced by alkyl groups; this has the effect of producing a blue or violet shade, which becomes deeper as the number of groups increases (see Dyeing).

<< Fuchsia

Lago Di Fucino >>


Got something to say? Make a comment.
Your name
Your email address