Reacción #160846

Ecuación de reacción

NaOH

Chlorosulfonyl isocyanate

pyrrole

DMF

→

above compound

Rendimiento 73.2%

1H-pyrrole-2,4-dicarbonitrile

Rendimiento 73.2%

Disolventes

EtOAc

ACN

ACN

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawas cooled in an ice/salt bath
2. 2
   workup.ADDITIONadded to the reaction dropwise over the following 30 min
3. 3
   OtroThe ice/salt bath was removed
4. 4
   TemperaturaThe solution was then cooled in an ice/salt bath
5. 5
   Temperaturato slowly warm to rt over 17 h
6. 6
   TemperaturaThe solution was cooled in an ice/salt bath
7. 7
   OtroThe solution was transferred to a separatory funnel
8. 8
   Otrothe organic layer was isolated
9. 9
   Extracciónthe aqueous layer was back extracted with EtOAc (2×)
10. 10
    LavadoThe collected organic was washed with aq saturated NaHCO3
11. 11
    ExtracciónThe aqueous layers were back extracted with EtOAc (2×50 mL)
12. 12
    OtroThe combined organic layers were collected
13. 13
    Secadodried (MgSO4)
14. 14
    Concentraciónconcentrated onto silica gel
15. 15
    Otropurified by column chromatography (9:1 v/v CH2Cl2-EtOAc)

Procedimiento

To a solution of ACN (15 mL) was added pyrrole (1.03 mL, 14.9 mmol) which was cooled in an ice/salt bath. Chlorosulfonyl isocyanate (2.73 mL, 31.3 mmol) was diluted in ACN (5 mL) and then added to the reaction dropwise over the following 30 min. The ice/salt bath was removed and the solution was allowed to warm to rt over the next 1.5 h. The solution was then cooled in an ice/salt bath and DMF (5.00 mL, 65.0 mmol) was slowly added via an addition funnel. The solution was allowed to slowly warm to rt over 17 h. The solution was cooled in an ice/salt bath and aq 1 N NaOH (50 mL) was added followed by EtOAc (50 mL). The solution was transferred to a separatory funnel, and the organic layer was isolated and the aqueous layer was back extracted with EtOAc (2×). The collected organic was washed with aq saturated NaHCO3 followed by H2O (100 mL). The aqueous layers were back extracted with EtOAc (2×50 mL). The combined organic layers were collected, dried (MgSO4), concentrated onto silica gel, and purified by column chromatography (9:1 v/v CH2Cl2-EtOAc) to afford 1.28 g of the above compound as a white solid (10.9 mmol, yield 73%). 1H-NMR (DMSO-d6) δ 13.29 (br s, 1H), 8.00 (s, 1H), 7.49 (s, 1H); LCMS RT=1.65 min.

Fuente