Phosphorus tribromide → 1-(Bromomethyl)-2,5-dimethoxy-3,4,6-trimethylbenzene
Reaction equation
[CH3:1][O:2][C:3]1[C:10]([CH3:11])=[C:9]([CH3:12])[C:8]([O:13][CH3:14])=[C:7]([CH3:15])[C:4]=1[CH2:5]O.P(Br)(Br)[Br:17]>O1CCCC1.O>[CH3:1][O:2][C:3]1[C:10]([CH3:11])=[C:9]([CH3:12])[C:8]([O:13][CH3:14])=[C:7]([CH3:15])[C:4]=1[CH2:5][Br:17]Participants
5
Procedure
A solution of 16.5 g (78.5 mmol) of 2,5-dimethoxy-3,4,6-trimethylbenzylalcohol in 90 ml of tetrahydrofuran was cooled to 0° C., to which 14.2 g (52.5 mmol) of phosphorus tribromide was added with stirring. After stirring at the same temperature for 30 minutes, the reaction mixture was diluted with water and extracted with isopropyl ether. The extract was washed with a saturated aqueous solution of sodium hydrogen carbonate and dried, from which the solvent was evaporated off. The residue was crystallized from methanol, to give 17.2 g (80.0%) of 2,5-dimethoxy-3,4,6-trimethylbenzyl bromide. m.p. 71°-72° C.
Workup
- additionwas added
- stirringAfter stirring at the same temperature for 30 minutes
- extractionextracted with isopropyl ether
- washThe extract was washed with a saturated aqueous solution of sodium hydrogen carbonate
- customdried, from which the solvent
- customwas evaporated off
- customThe residue was crystallized from methanol
Sources & evidence
- ORD record
- ord-0583784dd1fd4e7b9723037973ac6773
- Source dataset
- uspto-grants-1992_04
- Patent number
- US05106858
Reaction notes
Loading…