Reacción #7940

Ecuación de reacción

methyl (2E)-3-[4-(9a-butyl-7-methoxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoate

pyridine hydrochloride

pyridine hydrochloride

→

(2E)-3-[4-(9a-butyl-7-hydroxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothat condensed on the sides of the flask
2. 2
   Temperaturathe reaction mixture was cooled to room temperature
3. 3
   Otropartitioned between EtOAc (10 mL) and water (10 mL)
4. 4
   ExtracciónThe aqueous phase was extracted with more EtOAc (2×5 mL)
5. 5
   LavadoThe combined EtOAc extracts were washed with brine
6. 6
   Secadodried over MgSO4
7. 7
   Filtraciónfiltered
8. 8
   Otroevaporated under vacuum to a yellow solid (55 mg)
9. 9
   Extracciónextracted with 5% NaHCO3 (5 mL)
10. 10
    Extracciónextracted with EtOAc (2×5 mL)
11. 11
    Lavadowashed with brine
12. 12
    Secadodried over MgSO4
13. 13
    Filtraciónfiltered
14. 14
    Otroevaporated under vacuum to a yellow solid (39.4 mg)
15. 15
    OtroThis material was triturated with diethyl ether
16. 16
    Otrodried under vacuum

Procedimiento

A mixture of methyl (2E)-3-[4-(9a-butyl-7-methoxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoate (60 mg, 92% weight pure, 0.128 mmol) and pyridine hydrochloride (741 mg, 6.41 mmol) was placed under a nitrogen atmosphere, heated in an oil bath at 190° C., and stirred. The reaction flask was periodically dipped deeper into the heating bath in order to melt the pyridine hydrochloride that condensed on the sides of the flask. After 2 hours at 190° C., the reaction mixture was cooled to room temperature and partitioned between EtOAc (10 mL) and water (10 mL). The aqueous phase was extracted with more EtOAc (2×5 mL). The combined EtOAc extracts were washed with brine, dried over MgSO4, filtered, and evaporated under vacuum to a yellow solid (55 mg). The crude product was suspended in EtOAc (10 mL) and extracted with 5% NaHCO3 (5 mL). The NaHCO3 solution was acidified with 2N HCl (2.5 mL) and extracted with EtOAc (2×5 mL). The latter EtOAc extracts were combined, washed with brine, dried over MgSO4, filtered, and evaporated under vacuum to a yellow solid (39.4 mg). This material was triturated with diethyl ether and dried under vacuum to afford (2E)-3-[4-(9a-butyl-7-hydroxy-3-oxo-2,3,9,9a-tetrahydro-1H-fluoren-4-yl)phenyl]-2-propenoic acid as a pale yellow solid.

Fuente