反应详情

73.2 g of 3-(p-tert.butyl-phenyl)-2-methyl-allyl alcohol nd 8.6 ml of pyridine in 700 ml of n-pentane are cooled down to -5° C. At this temperature there are added dropwise while stirring over a period of 2 hours 15.2 ml of phosphorus tribromide in 700 ml of n-pentane and the mixture is stirred at room temperature for 3 hours. The mixture is poured on to 500 g of ice and stirred up for 30 minutes. The pentane phase is separated and the aqueous phase is back-extracted with n-pentane. The combined n-pentane phases are washed neutral with saturated sodium bicarbonate solution and water, dried over sodium sulphate and evaporated. The 3-(p-tert.butyl-phenyl)-2-methyl-allyl bromide, distilled in a high vacuum, boils at 123° C./0.01 Torr.

1. additionAt this temperature there are added dropwise
2. stirringstirred up for 30 minutes
3. customThe pentane phase is separated
4. extractionthe aqueous phase is back-extracted with n-pentane
5. washThe combined n-pentane phases are washed neutral with saturated sodium bicarbonate solution and water
6. dry with materialdried over sodium sulphate
7. customevaporated
8. distillationThe 3-(p-tert.butyl-phenyl)-2-methyl-allyl bromide, distilled in a high vacuum, boils at 123° C./0.01 Torr