Hydrochloric Acid → HCID 11194747, compound

1.66 g (10 mmol) of 5-amino-1-ethyl-2-nitrobenzene (2) are dissolved in a 60° C. mixture of 5 ml of conc. HCl and 25 ml H2O and cooled rapidly in an ice bath. At a temperature below 5° C., diazotisation is carried out with 760 mg (11 mmol) of sodium nitrite in 10 ml of H2O. After 10 minutes, a pinch of urea from a spatula is added and the mixture stirred for another 5 minutes in the ice bath. This reaction mixture is poured into an 80° C. solution of 1.5 g of copper(I) chloride in 10 ml of conc. HCl and 5 ml H2O which results in considerable evolvement of gas. The solution is held at this temperature for another 30 min. After cooling, the reaction solution is extracted three times with 50 ml each of EE and the combined organic phases washed with 50 ml each of NaOH and H2O. After drying over Na2SO4, concentration by means of a rotary evaporator is carried out. The crude product is placed on silica gel and purified by flash chromatography (40 g of silica gel, 3.5×13 cm, LM: PE). 863 mg (4.6 mmol, 46%) of (6) are obtained as a yellow oil.

1. temperaturecooled rapidly in an ice bath
2. customAt a temperature below 5° C., diazotisation
3. customresults in considerable evolvement of gas
4. waitThe solution is held at this temperature for another 30 min
5. temperatureAfter cooling
6. extractionthe reaction solution is extracted three times with 50 ml each of EE
7. washthe combined organic phases washed with 50 ml each of NaOH and H2O
8. dry with materialAfter drying over Na2SO4, concentration by means of a rotary evaporator
9. custompurified by flash chromatography (40 g of silica gel, 3.5×13 cm, LM: PE)

ORD record

ord-1c524a7968c64662969d5cd312ce5f55

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06750335B2