Urea → HCID 22708675, compound

Temperature

50 °C

1.66 g (10 mmol) of 5-amino-1-ethyl-2-nitrobenzene (2) are dissolved in a mixture of 3 ml of conc. sulfuric acid and 20 ml of H2O heated to 50° C. and cooled rapidly in an ice bath. At a temperature below 5° C., the mixture is subjected to diazotisation with 760 mg (11 mmol) of sodium nitrite. 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 added to a solution of 2.5 g of potassium iodide (15 mmol) in 10 ml of H2O and stirred at room temperature for one hour. The reaction mixture is extracted three times with 50 ml of EE each and the combined organic phases washed once with 50 ml each of In NaOH arid 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). 1.57 g (5.7 mmol, 57%) of (8) are obtained as a red oil.

1. temperaturecooled rapidly in an ice bath
2. customAt a temperature below 5° C.
3. extractionThe reaction mixture is extracted three times with 50 ml of EE each and the combined organic phases
4. washwashed once with 50 ml each of In NaOH arid H2O
5. dry with materialAfter drying over Na2SO4, concentration by means of a rotary evaporator
6. custompurified by flash chromatography (40 g of silica gel, 3.5×13 cm, LM: PE)

ORD record

ord-d09d14b8393b4ef7b035276d0d93056c

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06750335B2