反应详情

温度

4 °C

2 g (11.77 mmol) of 2,4-dimethoxybenzyl alcohol (Aldrich, Steinheim, FRG) are dissolved in 30 ml of abs. toluene, and this solution is untreated with 0.3 ml of pyridine. The clear solution is cooled down to approximately 4° C. and 1.12 ml (0.992 equivalents) of PBr3 in 6 ml of abs. toluene are added dropwise to it over the space of 30 min. After a further 45 min, the reaction solution is poured onto ice-water and the whole is extracted with ether. The organic phase is washed, in succession, with water, sat. sodium bicarbonate solution and saline (all being cold). The combined aqueous phases are reextracted with ether. The combined organic phases are dried over Na2SO4 and the ether is removed on a RE at about 30° C. The toluene solution which remains, and which contains the title compound, is immediately subjected to further use. TLC (hexane:ethyl acetate, 1:1): decomposition.

1. additionthe reaction solution is poured onto ice-water
2. extractionthe whole is extracted with ether
3. washThe organic phase is washed, in succession, with water, sat. sodium bicarbonate solution and saline (all being cold)
4. dry with materialThe combined organic phases are dried over Na2SO4
5. customthe ether is removed on a RE at about 30° C