2,2'-Dibromodiethyl ether

2,2'-dibromodiethyl ether is an important organic intermediate (building block) to synthetize substituted diethyl ether products.

111-46-6

5414-19-7

General procedure for the synthesis of 2,2'-dibromodiethyl ether from diethylene glycol: 21.2 g (0.2 mol) of diethylene glycol was added to a dry 1 L three-necked flask, followed by the addition of 500 mL of carbon tetrachloride as a solvent, and a magnetic stirrer was turned on to dissolve the ingredients completely. The reaction system was cooled in an ice-water bath to 0 °C. Under stirring conditions, 60 g (0.22 mol) of phosphorus tribromide was slowly added dropwise using a constant-pressure dropping funnel, with the rate of dropwise acceleration being controlled to avoid intense exotherm. After the dropwise addition, the reaction was continued in an ice-water bath with stirring for 1 hour. Subsequently, the ice-water bath was withdrawn and the reaction mixture was allowed to warm up naturally to room temperature with continuous stirring for 15 h to ensure complete reaction. Upon completion of the reaction, the carbon tetrachloride solvent was removed by concentration under reduced pressure by rotary evaporator. To the residue, 500 mL of ethyl acetate was added for dissolution, followed by four washes with 5% aqueous sodium carbonate to neutralize the residual acid. The organic layer was separated and dried with anhydrous sodium sulfate. Finally, the ethyl acetate was removed by distillation under reduced pressure to give 41.4 g of the target product 2,2'-dibromodiethyl ether as a colorless oil.