Viola throne

Structural formula
General
Surname	Viola throne
other names	Anthra [9,1,2- cde ] benzo [ rst ] pentaphen-5,10-dione ( IUPAC ); Nonacyclo [18.10.2.2 2.5 .0 3.16 .0 4.13 .0 6.11 .0 17.31 .0 22.27 .0 28.32 ] tetratriaconta-1 (31), 2.4, 6,8,10, 13,15,17,19,22,24,26,28 (32), 29,33-hexadecene-12,21-dione; CI Vat Blue 20; Violanthren-5,10-dione; Dibenzanthrone;
Molecular formula	C 34 H 16 O 2
Brief description	blue-black to black powder
External identifiers / databases
EC number	204-152-0
ECHA InfoCard	100.003.775
PubChem	8317
ChemSpider	8015
Wikidata	Q17093626
properties
Molar mass	456.5 g mol −1
Physical state	firmly
Melting point	490-495 ° C (decomposition)
solubility	in water <1000 mg l −1 at 19 ° C
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 302-315-319-335
	P: 261-305 + 351 + 338
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Violanthron ( CI Vat Blue 20 ) is a quinoid polycyclic aromatic hydrocarbon . The compound belongs to the carbonyl dyes and is used as a vat dye .

Manufacturing

Starting from benzanthrone ( 1 ), a mesomeric-stabilized anion ( 2 ) is obtained under basic conditions , which dimerizes spontaneously in the presence of an oxidizing agent . The dimerization product ( 4 ) can cyclize under alkaline conditions and a temperature of 180-225 ° C. to form violanthrone ( 5 ) .

Synthesis of violant throne from benzanthrone

Black vat dyes are obtained by nitrating Violanthron, although the exact number and substitution sites of the nitro groups is not known. The nitro compound can be reduced to the corresponding amine derivative , the dye CI Vat Green 9.

Web links

Commons : Violanthron - Collection of images, videos and audio files

Individual evidence

↑ ^a ^b ^c Chemical Datasheet Vat Blue 20. Cameo Chemicals, accessed March 20, 2019 .
↑ ^a ^b SAFETY DATA SHEET (A193981). Ambeed, Inc., accessed March 20, 2019 .
^ ^A ^b Heinrich Zollinger: Color Chemistry: Syntheses, Properties, and Applications of Organic Dyes and Pigments . 3. Edition. WILEY-VCH Verlag, Weinheim 2003, ISBN 3-906390-23-3 , p. 291 ff . ( limited preview in Google Book search).

[CAMEO-1] Chemical Datasheet Vat Blue 20. Cameo Chemicals, accessed March 20, 2019 .

[Ambeed-2] SAFETY DATA SHEET (A193981). Ambeed, Inc., accessed March 20, 2019 .

[Zollinger-3] A ^b Heinrich Zollinger: Color Chemistry: Syntheses, Properties, and Applications of Organic Dyes and Pigments . 3. Edition. WILEY-VCH Verlag, Weinheim 2003, ISBN 3-906390-23-3 , p. 291 ff . ( limited preview in Google Book search).