1,2-Bis(bromomethyl)benzene Chemical Properties

Melting point:

91-94 °C(lit.)

Boiling point:

140 °C / 20mmHg

Density 

1.96 g/mL at 25 °C(lit.)

refractive index 

1.6113 (estimate)

storage temp. 

Keep in dark place,Sealed in dry,Room Temperature

solubility 

sol ethanol, ether, chloroform; slightly sol petroleum ether.

form 

Crystals or Crystalline Powder

color 

White to light cream

Water Solubility 

soluble, hydrolyses

BRN 

637159

InChIKey

KGKAYWMGPDWLQZ-UHFFFAOYSA-N

CAS DataBase Reference

91-13-4(CAS DataBase Reference)

NIST Chemistry Reference

Benzene, 1,2-bis(bromomethyl)-(91-13-4)

EPA Substance Registry System

Benzene, 1,2-bis(bromomethyl)- (91-13-4)

Safety Information

Hazard Codes 

C

Risk Statements 

22-34

Safety Statements 

26-36/37/39-45

RIDADR 

UN 3448 6.1/PG 2

WGK Germany 

2

F 

8-19-21

TSCA 

Yes

HazardClass 

8

PackingGroup 

III

HS Code 

29036990

MSDS

• Language:English Provider:1,2-Bis(bromomethyl)benzene
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1,2-Bis(bromomethyl)benzene Usage And Synthesis

Chemical Properties

white to light yellow crystal powde

Uses

1,2-Bis(bromomethyl)benzene is used in the synthesis of isothioureas involved in the inhibition of human nitric oxide synthases. Also used in the synthesis of tridentate carbene ligands.

Application

1,2-Bis(bromomethyl)benzene (α,α′-Dibromo-o-xylene) is a source of o-quinodimethane, a highly reactive diene useful in Diels-Alder reactions; an electrophile for the synthesis of carbo- and heterocyclic compounds including macrocycles (cyclophanes, crown ethers, hemispherands, spherands), cryptands, hemicarcerands, vaulted cappedophanes, bicyclic compounds, spirocyclic compounds; a protective group reagent for diols.

Synthesis

General procedure for the synthesis of 2-methylbenzyl bromide and 1,2-bis(bromomethyl)benzene from o-xylene: To a mixture of N-bromosuccinimide (NXS) and substrate (o-xylene or its derivatives) in acetonitrile (CH3CN) at room temperature, silicon tetrachloride (SiCl4) was slowly added, and the reaction mixture was stirred continuously until thin layer chromatography (TLC) monitoring showed that the feedstock completely disappeared. Upon completion of the reaction, the reaction mixture was poured into water (H2O) and extracted with dichloromethane (CH2Cl2). All organic phase extracts were combined and dried with anhydrous magnesium sulfate (MgSO4) followed by evaporation under reduced pressure to remove the solvent. The resulting residue can be purified by recrystallization (using a solvent mixture of petroleum ether-ether (3:1)) to give pure 2-methylbenzyl bromide or 1,2-bis(bromomethyl)benzene or by silica gel column chromatography (using hexane-ethyl acetate (10:1 or 30:1) as eluent) to give the target product.

storage

1,2-Bis(bromomethyl)benzene should be avoided moisture; corrosive (forms HBr on hydrolysis); lachrymator; not mutagenic in Ames test; decontaminate by soaking apparatus, etc. in alcoholic alkali for 24 h or longer.

Purification Methods

Crystallise it from CHCl3 or pet ether, and/or distil it under vacuum. [Wenner Org Chem 17 527 1952, Beilstein 5 H 366, 5 I 180, 5 II 285, 5 III 819, 5 IV 929.]

References

[1] Tetrahedron Letters, 2006, vol. 47, # 40, p. 7245 - 7247
[2] Journal of Organic Chemistry, 1998, vol. 63, # 17, p. 6023 - 6026
[3] Journal of Organic Chemistry, 1998, vol. 63, # 17, p. 6023 - 6026
[4] Tetrahedron Letters, 2011, vol. 52, # 31, p. 4026 - 4029
[5] Chemistry Letters, 2004, vol. 33, # 7, p. 916 - 917

1,2-Bis(bromomethyl)benzene(91-13-4)Related Product Information

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