1-BROMO-3-ETHYLBENZENE

1-BROMO-3-ETHYLBENZENE Property

Melting point:

-20.49°C (estimate)

Boiling point:

85 °C

Density 

1,3493 g/cm³

refractive index 

1.5465

Flash point:

76-78°C/10mm

storage temp. 

Sealed in dry,Room Temperature

solubility 

Chloroform (Slightly), Ethyl Acetate (Slightly), Methanol (Slightly)

form 

Oil

color 

Clear Colorless

CAS DataBase Reference

2725-82-8(CAS DataBase Reference)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

26-36/37/39-37/39

HS Code 

2903998090

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

1-BROMO-3-ETHYLBENZENE Chemical Properties,Usage,Production

Chemical Properties

Clear colourless to light yellow liquid

Uses

1-Bromo-3-ethylbenzene is a useful synthetic intermediate. 1-Bromo-3-ethylbenzene is also used as a reagent to synthesize novel benzo[1,4]diazepin-2-one derivatives, which act as Endothelin receptor agonists and can possibly be used to reduce arterial blood pressure in humans.

Synthesis

The general procedure for synthesizing 3-bromoethylbenzene from 3-ethylaniline is as follows:Reference Example 1 Synthesis of 1-bromo-3-ethylbenzene. To a 50% aqueous sulfuric acid solution (43.6 g) containing 3-ethylaniline (10.0 g, 82.5 mmol), an aqueous sodium nitrite solution (16.5 mL containing 6.83 g, 99.0 mmol) was slowly added dropwise at 0°C, and the dropwise process lasted for 30 minutes. The resulting reaction mixture was continued to be stirred at 0°C for 45 min. Subsequently, the prepared diazonium salt solution was added in batches to a 48% hydrobromic acid solution (82.5 mL) containing copper(I) bromide (12.4 g, 86.6 mmol) while maintaining a mild reflux condition. After addition, the reaction mixture was heated to reflux for 30 minutes. Upon completion of the reaction, the mixture was cooled to room temperature and extracted with ether. The extract was washed sequentially with 1N aqueous sodium hydroxide and saturated brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography (eluent: hexane/ethyl acetate=20:1) to give 3-bromoethylbenzene (6.13 g, 40% yield) as an oil.1H-NMR (CDCl3) δ: 1.23 (3H, t, J=7.5 Hz), 2.63 (2H, q, J=7.5 Hz), 7.11-7.20 (2H, m). 7.28-7.38 (2H, m).

References

[1] Patent: EP1354603, 2003, A1
[2] Patent: EP1402900, 2004, A1
[3] Patent: EP1402900, 2004, A1
[4] Patent: EP1364949, 2003, A1. Location in patent: Page/Page column 78
[5] Patent: EP1205478, 2002, A1