3-bromopyrocatechol

Structural formula
General
Surname	3-bromopyrocatechol
other names	3-bromobenzene-1,2-diol; 3-bromo-1,2-dihydroxybenzene;
Molecular formula	C 6 H 5 BrO 2
External identifiers / databases
EC number	681-061-6
ECHA InfoCard	100.206.236
PubChem	26659
ChemSpider	24835
Wikidata	Q223053
properties
Molar mass	189.01 g mol −1
Physical state	firmly
Melting point	39-42 ° C
boiling point	118–120 ° C (12 h Pa )
pK s value	9.40
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 315-319-335
	P: 261-280-304 + 340-305 + 351 + 338-405-501
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

3-bromopyrocatechol is a chemical compound that belongs to the group of phenols . It is one of the two positionally isomeric monobromo derivatives of catechol (1,2-hydroxybenzene) alongside 4-bromopychol . It crystallizes in needles.

presentation

3-bromopyrocatechol can be obtained from 2,3- dimethoxybromobenzene , which can be obtained from veratrole , by reacting it with aluminum chloride in chlorobenzene .

The synthesis from 2- bromophenol is also possible.

Analytical evidence

For qualitative analytical proof, the bromination with potassium bromide and bromine produces the tetrabromo derivative , which has a melting point of 192 ° C.

Simple methylation with dimethyl sulfate leads to 2-bromo-6-methoxyphenol (6- bromoguajacol , CAS number: 28165-49-3), the melting point of which is 63 ° C.

Complete methylation leads to 1-bromo-2,3-dimethoxybenzene (3- bromveratrol , CAS number: 5424-43-1), which has a boiling point of 114 ° C at 5 mm Hg.

Individual evidence

↑ ^a ^b ^c data sheet 3-bromopyrocatechol from AlfaAesar, accessed on April 30, 2017 ( PDF )(JavaScript required) .
^ ^A ^b ^c Howard S. Mason: "The allergenic Principles of Poison Ivy. VI. Note on the Synthesis of 3-Substituted Catechols", in: J. Am. Chem. Soc. , 1947 , 69 (9), pp. 2241-2242; doi: 10.1021 / ja01201a514 .
↑ ^a ^b ^c Dictionary of organic compounds , p. 932 ( limited preview in Google book search).
↑ TV Hansen, L. Skattebøl: "One-pot synthesis of substituted catechols from the corresponding phenols", in: Tetrahedron Letters , 2005 , 46 (19), pp. 3357-3358; doi: 10.1016 / j.tetlet.2005.03.082 .
^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 331.
^ Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 653.

[ALFA-1] ta sheet 3-bromopyrocatechol from AlfaAesar, accessed on April 30, 2017 ( PDF )(JavaScript required) .

[Mason-2] A ^b ^c Howard S. Mason: "The allergenic Principles of Poison Ivy. VI. Note on the Synthesis of 3-Substituted Catechols", in: J. Am. Chem. Soc. , 1947 , 69 (9), pp. 2241-2242; doi: 10.1021 / ja01201a514 .

[DOC-3] Dictionary of organic compounds , p. 932 ( limited preview in Google book search).

[4] TV Hansen, L. Skattebøl: "One-pot synthesis of substituted catechols from the corresponding phenols", in: Tetrahedron Letters , 2005 , 46 (19), pp. 3357-3358; doi: 10.1016 / j.tetlet.2005.03.082 .

[5] Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 331.

[6] Association of authors: Organikum , 19th edition, Johann Ambrosius Barth, Leipzig · Berlin · Heidelberg 1993, ISBN 3-335-00343-8 , p. 653.