Methyl 2,5-Dibromopentanoate

Methyl 2,5-Dibromopentanoate Property

Boiling point:

93-95°C 1mm

Density 

1,746 g/cm³

storage temp. 

2-8°C

solubility 

Chloroform (Slightly, Sonicated), Methanol (Slightly)

form 

Oil

color 

Colourless

InChI

InChI=1S/C6H10Br2O2/c1-10-6(9)5(8)3-2-4-7/h5H,2-4H2,1H3

InChIKey

YVHCGWPKBSEBTH-UHFFFAOYSA-N

SMILES

C(OC)(=O)C(Br)CCCBr

Safety

Risk Statements 

36/37/38

Safety Statements 

26-36/37/39

HS Code 

2915705090

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

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

Methyl 2,5-Dibromopentanoate Chemical Properties,Usage,Production

Uses

Methyl 2,5-Dibromopentanoate can be used for liquid crystal compounds for display devices.

Synthesis

The general procedure for the synthesis of methyl 2,5-dibromovalerate from tetrahydro-2H-pyran-2-one and methanol was as follows: 518 g of 6-valerol and 5 ml of phosphorus tribromide were added to an 11-necked, three-necked flask. The mixture was heated to 95 °C to 105 °C under stirring conditions, followed by the slow addition of 550 g of bromine while controlling the reaction temperature between 100 °C and 120 °C. After the reaction system was stabilized, another 5 ml of phosphorus tribromide and 236 g of bromine were added at 110 °C. After the addition was completed, the reaction mixture was allowed to stand for 30 minutes and subsequently cooled to between 0°C and 10°C. Next, 11 ml of methanol and 1 g of p-toluenesulfonic acid were added to the reaction system and the reaction temperature was maintained at 25 °C. After refluxing the reaction mixture for 5 hours, the excess reagent was removed by distillation and the lower organic phase was isolated. The organic phase was washed sequentially with 500 ml of 10% sodium hydroxide solution and 500 ml of water. After the washing was completed, the organic layer was separated and purified by fractional distillation (139 °C to 142 °C/28 hPa) to give 612.7 g of methyl 2,5-dibromopentanoate in 45% yield and >96% GC purity.

References

[1] Chemical Communications, 2015, vol. 51, # 70, p. 13470 - 13473
[2] Patent: WO2005/28449, 2005, A1. Location in patent: Page/Page column 11
[3] Tetrahedron, 1998, vol. 54, # 19, p. 4991 - 5004