Hydrogen Bromide → Benzene, 1-bromo-3-ethyl-

Temperature

0 °C

To an aqueous 50% sulfuric acid solution (43.6 g) containing 3-ethylaniline (10.0 g, 82.5 mmol) was added dropwise an aqueous solution (16.5 mL) of sodium nitrite (6.83 g, 99.0 mmol) at 0° C. over 30 min. The obtained reaction mixture was stirred at 0° C. for 45 min. A solution of this diazonium salt was added by small portions to a 48% hydrobromic acid solution (82.5 mL) containing copper(I) bromide (12.4 g, 86.6 mmol) with heating under gentle reflux. After the addition, the reaction mixture was heated under reflux for 30 min. The reaction mixture was cooled to room temperature and extracted with ethyl ether. The extract was washed successively with 1N aqueous sodium hydroxide solution and saturated brine, filtered, dried and concentrated. The residue was purified by silica gel column chromatography (hexane-ethyl acetate=20:1) to give the title compound (6.13 g, yield 40%).

1. customThe obtained reaction mixture
2. temperaturewith heating under gentle reflux
3. additionAfter the addition
4. temperaturethe reaction mixture was heated
5. temperatureunder reflux for 30 min
6. temperatureThe reaction mixture was cooled to room temperature
7. extractionextracted with ethyl ether
8. washThe extract was washed successively with 1N aqueous sodium hydroxide solution and saturated brine
9. filtrationfiltered
10. customdried
11. concentrationconcentrated
12. customThe residue was purified by silica gel column chromatography (hexane-ethyl acetate=20:1)

ORD record

ord-3247d82f02414a87a654f376fc0538b9

Source dataset

uspto-grants-2007_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07199124B2