4,5-dibromopyrocatechol

Structural formula
General
Surname	4,5-dibromopyrocatechol
other names	4,5-dibromo-1,2-dihydroxybenzene; 4,5-dibromo-1,2-benzenediol; AmbsicLK-48;
Molecular formula	C 6 H 4 Br 2 O 2
Brief description	white crystals
External identifiers / databases
EC number	627-690-1
ECHA InfoCard	100.156.029
PubChem	223326
ChemSpider	193955
Wikidata	Q229847
properties
Molar mass	267,90 g · mol -1
Physical state	firmly
Melting point	111-116 ° C ; 122 ° C;
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 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 .

4,5-Dibromopyrocatechol is a chemical compound that belongs to both the phenols and the halogen aromatic compounds . It is isomeric to 3,5-dibromopyrocatechol and 3,6-dibromopyrocatechol .

presentation

4,5-Dibromopyrocatechol can be obtained from catechol by reacting it with elemental bromine in glacial acetic acid.

Reactions

Esterification with acetic anhydride produces the diacetate, which has a melting point of 110 ° C.

The dimethyl ether ( 4,5-dibromoveratrole ), which is obtained by reacting with dimethyl sulfate , has a melting point of 92 to 93 ° C.

Further bromination with 1 mole of bromine in glacial acetic acid leads to 3,4,5-tribromopyrocatechol (CAS number: 2747-17-3), the melting point of which is 139–141 ° C. Complete bromination gives tetrabromo-catechol .

use

4,5-Dibromopyrocatechol is used as a starting material for the synthesis of 4,5-disubstituted 1,2-dibromobenzenes . It is also the starting material for the production of 4,5-diether-substituted phthalonitriles via a Rosenmund-von Braun reaction .

Individual evidence

^ ^A ^b ^c Moritz Kohn: "Bromination of Catechol", in: J. Am. Chem. Soc. , 1951 , 73 (1), pp. 480-480; doi : 10.1021 / ja01145a519
↑ ^a ^b ^c data sheet 4,5-dibromobenzene-1,2-diol from Sigma-Aldrich , accessed on March 20, 2011 ( PDF ).
^ ^A ^b J. Buckingham: Dictionary of organic compounds, Volume 9, p. 1914 ( limited preview in the Google book search).
↑ ^a ^b ^c K. M. Kadish, R. Guilard, KM Smith: "The porphyrin handbook", Vol. 11-20, p. 14 ( limited preview in the Google book search).
↑ D. Ximing, X. Huijun: "The synthesis and film-forming property of a new amphiphilic phthalocyanine" in: Dyes and Pigments , 1998 , 39 (4) , pp. 223-229; doi : 10.1016 / S0143-7208 (98) 00005-9 .

[Kohn-1] A ^b ^c Moritz Kohn: "Bromination of Catechol", in: J. Am. Chem. Soc. , 1951 , 73 (1), pp. 480-480; doi : 10.1021 / ja01145a519

[Sigma-2] ta sheet 4,5-dibromobenzene-1,2-diol from Sigma-Aldrich , accessed on March 20, 2011 ( PDF ).

[DOC-3] A ^b J. Buckingham: Dictionary of organic compounds, Volume 9, p. 1914 ( limited preview in the Google book search).

[Kadish-4] K. M. Kadish, R. Guilard, KM Smith: "The porphyrin handbook", Vol. 11-20, p. 14 ( limited preview in the Google book search).

[5] D. Ximing, X. Huijun: "The synthesis and film-forming property of a new amphiphilic phthalocyanine" in: Dyes and Pigments , 1998 , 39 (4) , pp. 223-229; doi : 10.1016 / S0143-7208 (98) 00005-9 .