Croceic acid

Structural formula
General
Surname	Croceic acid
other names	7-hydroxynaphthalene-1-sulfonic acid; Baeyer's acid;
Molecular formula	C 10 H 8 O 4 S
External identifiers / databases
EC number	205-066-6
ECHA InfoCard	100.004.607
PubChem	67237
Wikidata	Q1140703
properties
Molar mass	224.23 g mol −1
Physical state	firmly
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 315-319
	P: ?
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Croceinsäure (also Croceïnsäure , 2-naphthol-8-sulfonic acid) is a monosulphonic acid (2: 8) of the β-naphthol .

history

In 1881 the “Friedr. Bayer & Co. Elberfeld ”, the predecessor company of Bayer AG , received their first German patent for the acid produced by Eugen Frank for the first time. It belongs to the letter acids .

Extraction and presentation

Croceic acid can be obtained by sulfonating 2-naphthol with chlorosulfonic acid or sulfuric acid. This creates the unstable 2-naphthol-1-sulfonic acid , which rearranges to croceic acid at lower temperatures. At temperatures of 100 ° C, this in turn rearranges to 2-naphthol-6-sulfonic acid .

Individual evidence

↑ Template: CL Inventory / not harmonized There is not yet a harmonized classification for this substance . A labeling of 7-hydroxynaphthalene-1-sulphonic acid in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on June 23, 2017, is shown, which is derived from a self-classification by the distributor .
↑ Crocein acid . In: Meyers Großes Konversations-Lexikon . 6th edition. Volume 4, Bibliographisches Institut, Leipzig / Vienna 1906, p. 349 .
↑ The Bavarian Cross is 100 years old - one of the most famous trademarks in the world. In: pressrelations.de. Bayer AG , January 5, 2004, accessed June 23, 2017 .
↑ Florian Dachs: Inventions and innovation processes in the empire . GRIN Verlag, 2005, ISBN 3-638-35873-9 , p. 25 ( limited preview in Google Book search).
↑ Amit Arora: Aromatic Organic Chemistry . Discovery Publishing House, 2006, ISBN 81-8356-202-7 , pp. 177 ( limited preview in Google Book search).
^ OP Agarwal: Synthetic Organic Chemistry: For Honors & Post-Graduate Students of Various Universities . Krishna Prakashan Media, 2006, p. 4 ( limited preview in Google Book search).
^ OP Agarwal: Natural Products . Krishna Prakashan Media, 2010, ISBN 81-85842-98-1 , p. 457 ( limited preview in Google Book search).

[1] Template: CL Inventory / not harmonized There is not yet a harmonized classification for this substance . A labeling of 7-hydroxynaphthalene-1-sulphonic acid in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on June 23, 2017, is shown, which is derived from a self-classification by the distributor .

[2] Crocein acid . In: Meyers Großes Konversations-Lexikon . 6th edition. Volume 4, Bibliographisches Institut, Leipzig / Vienna 1906, p. 349 .

[3] The Bavarian Cross is 100 years old - one of the most famous trademarks in the world. In: pressrelations.de. Bayer AG , January 5, 2004, accessed June 23, 2017 .

[Florian_Dachs-4] Florian Dachs: Inventions and innovation processes in the empire . GRIN Verlag, 2005, ISBN 3-638-35873-9 , p. 25 ( limited preview in Google Book search).

[Amit_Arora-5] Amit Arora: Aromatic Organic Chemistry . Discovery Publishing House, 2006, ISBN 81-8356-202-7 , pp. 177 ( limited preview in Google Book search).

[O._P._Agarwal-6] OP Agarwal: Synthetic Organic Chemistry: For Honors & Post-Graduate Students of Various Universities . Krishna Prakashan Media, 2006, p. 4 ( limited preview in Google Book search).

[Natural_Products-7] OP Agarwal: Natural Products . Krishna Prakashan Media, 2010, ISBN 81-85842-98-1 , p. 457 ( limited preview in Google Book search).