Methyl 2,5-Dibromopentanoate

518 g 6-VALEROLACTONE and 5 ml phosphorous tribromide were fed into a 11 three-necked flask. The mixture was heated up to a temperature of 95 °C to 105 °C under stirring and 550 g bromine were added, while the temperature was kept constant between 100 and 120 °C. Subsequently, 5 ml phosphorus tribromide and 236 g bromine were added at a temperature of 110 °C. After the reaction mixture had been allowed to stand for 30 minutes, it was cooled down to a temperature of 0 to 10 °C. Then, 11 methanol and lg p-toluenesulfonic acid were added, while the temperature was kept constant at 25 °C. After 5 hours of refluxing, the excess material was distilled off and the lower organic layer was separated. The organic layer was then washed with 500 ml of 10percent sodium hydroxide and 500 ml water. After separation of the organic layer, the product was isolated by fractional distillation (139 to 142 °C/28 hPa) and 612.7 g of the title compound were obtained (yield 45percent, purity > 96percent by GC).518 g 6-VALEROLACTONE and 5 ml phosphorous tribromide were fed into a 11 three-necked flask. The mixture was heated up to a temperature of 95 °C to 105 °C under stirring and 550 g bromine were added, while the temperature was kept constant between 100 and 120 °C. Subsequently, 5 ml phosphorus tribromide and 236 g bromine were added at a temperature of 110 °C. After the reaction mixture had been allowed to stand for 30 minutes, it was cooled down to a temperature of 0 to 10 °C. Then, 11 methanol and lg p-toluenesulfonic acid were added, while the temperature was kept constant at 25 °C. After 5 hours of refluxing, the excess material was distilled off and the lower organic layer was separated. The organic layer was then washed with 500 ml of 10percent sodium hydroxide and 500 ml water. After separation of the organic layer, the product was isolated by fractional distillation (139 to 142 °C/28 hPa) and 612.7 g of the title compound were obtained (yield 45percent, purity > 96percent by GC).

Molecular Weight:273.95
XLogP3:2.4
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:5
Exact Mass:273.90271
Monoisotopic Mass:271.90475
Topological Polar Surface Area:26.3
Heavy Atom Count:10
Complexity:106
Undefined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes