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

Temperature

0 °C

To a 50% aqueous sulfuric acid solution (43.6 g) of 3-ethylaniline (10.0 g, 82.5 mmol) was added dropwise at 0° C. an aqueous solution (16.5 mL) of sodium nitrite (6.83 g, 99.0 mmol) over 30 min. The obtained reaction mixture was stirred at 0° C. for 45 min. This diazonium salt solution was added by small portions to a 48% hydrobromic acid solution (82.5 mL) of copper(I) bromide (12.4 g, 86.6 mmol) being gently refluxed under heating. After the addition, the reaction mixture was refluxed under heating for 30 min. The reaction mixture was cooled to room temperature and extracted with ether. The extract was washed successively with 1N aqueous sodium hydroxide solution and saturated brine, filtrated, 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%). oil.

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

ORD record

ord-9c20f4d7d15a48acb2127c58bbb3ac17

Source dataset

uspto-grants-2005_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06962933B1