Vixen

Structural formula
General
Surname	Vixen
other names	4 - [(4-aminophenyl) - (4-imino-3-methylcyclohexa-2,5-dien-1-ylidene) methyl] aniline hydrochloride CI Basic Violet 14 CI 42510 Rosaniline chloride Aniline red Diamond fox Fuchsin basic Fuchsin RFN Magenta I. Magenta Methyl rosanilinium chloride Methyl fuchsine 3-methyl parafuchsin
Molecular formula	C 20 H 20 ClN 3
Brief description	green odorless solid
External identifiers / databases
CAS number 632-99-5 ( hydrochloride ) 3248-93-9 (free base) EC number 211-189-6 ECHA InfoCard 100.010.173 PubChem 12448 ChemSpider 10468578 Wikidata Q419167
properties
Molar mass	337.85 g mol −1
Physical state	firmly
Melting point	235 ° C (decomposition)
solubility	little in water (4 g l −1 at 25 ° C)
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 302-351 P: 281
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Color of fuchsine ( magenta )
color code: # ca1f7b

Fuchsin is a red-blue cationic triphenylmethane dye that is dissolved in alcohol ( ethanol ) and used for staining in microscopy and histology .

history

Fuchsin was discovered in 1858 by the German chemist August Wilhelm von Hofmann and almost at the same time by the Lyon chemist François-Emmanuel Verguin (patent, 1858) and by the Polish Jakub Natanson (1856) and named after the American ornamental plant fuchsia , whose blue-red flowers have a similar shade. It was the second large-scale tar dye .

presentation

Fuchsine crystals

Fuchsine is produced by reacting 4-aminobenzaldehyde , 4-aminobenzyl alcohol or 4,4'-diaminodiphenylmethane with aniline in the presence of oxidizing agents and iron (II) chloride . In addition to fuchsin, the impurity also produces parafuchsin , which has similar properties.

The representation from aniline, o -toluidine , p -toluidine and arsenic acid or nitrobenzene is also possible .

properties

Fuchsin in aqueous solution

Fuchsin forms green-yellow, metallic crystals that slowly dissolve in water and alcohol with an intense red color.

Commercially available fuchsin is a mixture of fuchsin itself - IUPAC name: 4 - [(4,4'-diamino) diphenylmethylene] cyclohexa-2,5-dienylidene ammonium chloride - and parafuchsin {4 - [(4,4'-diamino) diphenylmethylene] -2-methylcyclohexa-2,5-dienylidene ammonium chloride}. They differ in a methyl group and are therefore homologous .

The molecule is a mesomeric stabilized cation with the properties of a cyanine dye . This is the reason for the intense colors of the fuchsin. Alcoholic fuchsin solutions have an abnormal dispersion .

use

• Fuchsine has long been used as a dye for wool and leather.
• It is used in the Feulgen Nucleal Reaction to detect DNA in cell nuclei or in the nuclear equivalent of bacteria . It can also be used for chromosome staining.
• Fuchsine has an antifungal and antiseptic effect on gram-positive bacteria, but is not used in humans or in veterinary medicine because it is suspected of being carcinogenic .
• Fuchsin was first described as a trigger for bladder cancer in 1895 .
• Fuchsin was also used in color photography .
• Basic fuchsin has been used since the 1960s to stain microcracks in bones in vitro and to identify them with the fluorescence of the dye.
• Fuchsin is used in technology to detect cracks in components, e.g. B. fiber composite components used.
• Due to the existing open residual porosity in stoneware , which can be proven by the "Fuchsin test", a clear distinction can be made to porcelain .
• As a fuchsin sulphurous acid , it is used as a detection agent for aldehydes . A little dilute sulphurous acid is added to the magenta-colored solution of fuchsine until the liquid has become discolored. When added to an aldehyde, the solution turns blue and red to purple.

Individual evidence

1. ↑ ^{a b c d e f} Entry on magenta in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .
2. ↑ H. Gnamm, K. Grafe et al. a .: Handbook of Gerbereichemie und Lederfabrikation. Third volume: Das Leder , 1st part, Springer, 1936, ISBN 978-3-7091-2211-2 , p. 78.
3. ^ Siegfried Hauptmann : Organic chemistry. 2nd edition, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig 1985, ISBN 3-342-00280-8 , p. 758.
4. ↑ HM Frost: Presence of microscopic cracks in vivo in bone. In: Henry Ford Hospital Bulletin. 8, 1960, pp. 25-35.
5. ^ TC Lee, E. Myers & W. Hayes: Fluorescence-aided detection of microdamage in compact bone. In: Journal of Anatomy . 193 (02), 1998, pp. 179-184.
6. ^ Hermann Salmang : Ceramics. 7th edition, Springer-Verlag, Berlin / Heidelberg, 2007, ISBN 3-540-63273-5 , p. 705.

Web links

Commons : Fuchsin  - collection of images, videos and audio files

Wiktionary: Fuchsin  - explanations of meanings, word origins, synonyms, translations

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