反应详情

温度

0 °C

6.2 g of 4,4-dimethyl-6-(1-hydroxyethyl)chromane were dissolved in 3 ml of absolute ether and 20 ml of hexane and the solution was treated with 3 drops of pyridine. At a temperature of 0°-5° C. there was slowly added dropwise thereto a solution of 5.4 g of phosphorus tribromide in 20 ml of hexane. The mixture was stirred at 0° C. for a further 3 hours, poured onto ice and extracted with ether. The organic phase was washed with dilute sodium bicarbonate solution and water, dried over sodium sulphate and evaporated. There were obtained 4.5 g of 4,4-dimethyl-6-(1-bromoethyl)chromane in the form of a reddish oil which was converted into the phosphonium bromide without further purification.

1. additionAt a temperature of 0°-5° C. there was slowly added dropwise
2. additionpoured onto ice
3. extractionextracted with ether
4. washThe organic phase was washed with dilute sodium bicarbonate solution and water
5. dry with materialdried over sodium sulphate
6. customevaporated