Methylhydroquinone

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Structural formula
Structural formula of methylhydroquinone
General
Surname Methylhydroquinone
other names
  • 2,5-dihydroxytoluene
  • 2-methylhydroquinone
  • Tolyl hydroquinone
Molecular formula C 7 H 8 O 2
Brief description

white crystals

External identifiers / databases
CAS number 95-71-6
EC number 202-443-7
ECHA InfoCard 100.002.222
PubChem 7253
ChemSpider 6983
Wikidata Q1925586
properties
Molar mass 124.14 g mol −1
Physical state

firmly

Melting point

128-130 ° C

boiling point

285 ° C

solubility

soluble in water (77 g l −1 at 25 ° C)

safety instructions
GHS labeling of hazardous substances
07 - Warning

Caution

H and P phrases H: 302-315-319-335
P: 261-305 + 351 + 338
Toxicological data

200 mg kg −1 ( LD 50 ,  rat ,  ip )

As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Methylhydroquinone is an aromatic chemical compound that belongs to the group of dihydroxytoluenes , a group of six constitutional isomers . Their flash point is 172 ° C and self-ignition occurs at 468 ° C.

presentation

Methylhydroquinone ( 2 ) can be produced from o -cresol ( 1 ) by an Elbs oxidation :

Production of methylhydroquinone from o-cresol

use

Methylhydroquinone is used as a stabilizer for unsaturated polyesters and as an antioxidant for fatty esters. It prevents the formation of peroxides in ethers , chlorinated hydrocarbons and ethyl cellulose . It is also used as a starting material for the synthesis of pharmaceutical products.

Reactions

Bromination produces 2-bromo-5-methylhydroquinone .

Individual evidence

  1. ↑ a b Entry on Methylhydroquinone at chemicalland21.com, accessed on November 5, 2016.
  2. ↑ Data sheet methylhydroquinone from Sigma-Aldrich , accessed on November 5, 2016 ( PDF ).
  3. ^ Entry on 2-methylhydroquinone at ChemicalBook , accessed April 18, 2012.
  4. ↑ a b c d e Entry on 2-methylhydroquinone in the GESTIS substance database of the IFA , accessed on February 10, 2017(JavaScript required) .
  5. ↑ K. Elbs: "About Nitrohydroquinone", in: J. Prakt. Chem. , 1893 , 48  (1), pp. 179-185; doi : 10.1002 / prac.18930480123 .
  6. ↑ External identifiers or database links for 2-bromo-5-methylhydroquinone : CAS number: 67289-05-8, EC number: 666-237-2, ECHA InfoCard: 100.192.321 , PubChem : 334077 , ChemSpider : 296033 , Wikidata : Q82075177 .
  7. ↑ Larry L. Miller, Ray F. Stewart: “Catalyzed addition of trimethylsilyl halides to quinones. Direct preparation of halohydroquinones and their silyl ethers ", in: Journal of Organic Chemistry , 1978 , 43  (15), pp. 3078-3079; doi : 10.1021 / jo00409a039 .