Reaction #452428

Reaction equation

4-toluenesulfonyl chloride

N-ethyl-N'-3-(1-pyrrolidinyl)propylurea

triethylamine

→

desired product

Yield 67.0%

1-(3-(1-pyrrolidinyl)propyl)-3-ethylcarbodiimide

Yield 67.0%

Solvents

dichloromethane

dichloromethane

Conditions

Workup

1. 1
   Temperatureto maintain
2. 2
   Otherthe reaction at 0-5° C
3. 3
   workup.ADDITIONAfter the addition
4. 4
   Temperaturethe reaction mixture was warmed to room temperature
5. 5
   Temperatureheated
6. 6
   Temperatureto reflux for 4 hours
7. 7
   TemperatureAfter cooling to room temperature
8. 8
   Washthe reaction mixture was washed with saturated aqueous potassium carbonate (3×150 mL)
9. 9
   Extractionextracted with dichloromethane
10. 10
    Concentrationconcentrated under reduced pressure
11. 11
    Otherthe solution decanted off from the solid
12. 12
    Concentrationconcentrated under reduced pressure

Procedure

To a solution of 31.0 gm (0.156 mole) N-ethyl-N'-3-(1-pyrrolidinyl)propylurea in 500 mL dichloromethane were added 62.6 gm (0.62 mole) triethylamine and the solution was cooled to 0° C. To this solution were then added 59.17 gm (0.31 mole) 4-toluenesulfonyl chloride in 400 mL dichloromethane dropwise at such a rate as to maintain the reaction at 0-5° C. After the addition was complete, the reaction mixture was warmed to room temperature and then heated to reflux for 4 hours. After cooling to room temperature, the reaction mixture was washed with saturated aqueous potassium carbonate (3×150 mL). The aqueous phases were combined and extracted with dichloromethane. All organic phases were combined and concentrated under reduced pressure. The resultant orange slurry was suspended in 250 mL diethyl ether and the solution decanted off from the solid. The slurry/decantation process was repeated 3 more times. The ether solutions were combined and concentrated under reduced pressure to give 18.9 gm (67%) of the desired product as a crude orange oil. A portion of the oil was distilled under vacuum to give a colorless oil distilling at 78-82° C. (0.4 mm Hg).

Source