反应详情

温度

0 °C

To a solution of 3,4,5-trimethoxybenzyl alcohol (20.2 g, 0.108 mol) in 300 ml of dry tetrahydrofuran was added 4.12 ml (0.052 mol) of pyridine, and cooled to 0° C. A solution of phosphorous tribromide (4.8 ml, 0.051 mol) in 20 ml of dry tetrahydrofuran was added dropwise to the above solution at 0 ° C. The mixture was stirred for 1 hr. Tetrahydrofuran was concentrated. The residue was then diluted with 200 ml of 10% hydrochloric acid, and then extracted with 200 ml of ethyl acetate. The extract was dried over magnesium sulfate, filtered, concentrated, and dried in vacuum overnight. 3,4,5-Trimethoxybenzyl bromide (27 g, 100% yield) was obtained as a white solid, which can be used without further purification.

1. concentrationTetrahydrofuran was concentrated
2. additionThe residue was then diluted with 200 ml of 10% hydrochloric acid
3. extractionextracted with 200 ml of ethyl acetate
4. dry with materialThe extract was dried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. customdried in vacuum overnight