Phosphorus tribromide → 2-Bromo-6-(bromomethyl)naphthalene

To a three-necked flask (2 L) was added (6-bromonaphthalen-2-yl)methanol (47.7 g, 0.201 mol) and chloroform (600 ml). The mixture was then cooled with an ethanol-liquid nitrogen bath to −35□. To the suspension was added phosphorus tribromide (28.6 ml, 0.603 mol) dropwise slowly over 25 minutes. The cooling bath was removed and the reaction mixture was kept under stirring for additional 2.5 hours at room temperature. The mixture was cooled again and to it was added methanol (250 mL) dropwise slowly and released quickly was hydrogen bromide, which was absorbed with a potassium hydrate solution. The mixture was warmed to room temperature and the resulting precipitate was collected by filtering under reduced pressure. The filter cake was washed with ethanol and dried to afford a white solid, 2-bromo-6-(bromomethyl)naphthalene (35 g).

1. temperatureThe mixture was then cooled with an ethanol-liquid nitrogen bath to −35□
2. customThe cooling bath was removed
3. temperatureThe mixture was cooled again and to it
4. additionwas added methanol (250 mL) dropwise slowly
5. customwas absorbed with a potassium hydrate solution
6. temperatureThe mixture was warmed to room temperature
7. customthe resulting precipitate was collected
8. filtrationby filtering under reduced pressure
9. washThe filter cake was washed with ethanol
10. customdried

ORD record

ord-67e38b1f9afa422596f00e4e51fad340

Source dataset

uspto-grants-2014_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08872422B2