Réaction #2487472

Équation de réaction

tert-butyl[2-(2-hydroxy-3-methylpentyl)-4-methoxyphenyl]carbamate

trifluoroacetic acid

→

title compound

Rendement 87.7%

2-(Butan-2-yl)-5-methoxy-1H-indole

Rendement 87.7%

Solvants

dichloromethane

Conditions de réaction

Traitement

1. 1
   Températurecooling
2. 2
   ConcentrationThe reaction mixture was concentrated under reduced pressure
3. 3
   workup.ADDITIONTo the residue were added ethyl acetate and saturated aqueous sodium hydrogen carbonate solution
4. 4
   Autreto separate the organic layer
5. 5
   LavageThe organic layer was washed with water and saturated brine successively
6. 6
   Séchagedried over anhydrous sodium sulfate
7. 7
   Concentrationconcentrated under reduced pressure
8. 8
   workup.DISSOLUTIONUnder an argon atmosphere, the residue was dissolved in N,N-dimethylformamide (30 mL)
9. 9
   workup.ADDITION2-bromomesitylene (1.50 mL), tetrakis(triphenylphosphine) palladium(0) (472 mg), and potassium carbonate (2.25 g) were added
10. 10
    workup.STIRRINGThe mixture was stirred overnight at 150° C
11. 11
    TempératureThe reaction mixture was cooled to room temperature
12. 12
    workup.ADDITIONwater was added
13. 13
    Extractionfollowed by extraction with ethyl acetate
14. 14
    LavageThe organic layer was washed with water and saturated brine successively
15. 15
    Séchagedried over anhydrous magnesium sulfate
16. 16
    Concentrationconcentrated under reduced pressure
17. 17
    AutreThe residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane)

Mode opératoire

To a solution of tert-butyl[2-(2-hydroxy-3-methylpentyl)-4-methoxyphenyl]carbamate (2.65 g) in dichloromethane (25 mL) was added trifluoroacetic acid (5 mL) under ice-cooling. This mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure. To the residue were added ethyl acetate and saturated aqueous sodium hydrogen carbonate solution to separate the organic layer. The organic layer was washed with water and saturated brine successively, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. Under an argon atmosphere, the residue was dissolved in N,N-dimethylformamide (30 mL), and then 2-bromomesitylene (1.50 mL), tetrakis(triphenylphosphine) palladium(0) (472 mg), and potassium carbonate (2.25 g) were added thereto. The mixture was stirred overnight at 150° C. The reaction mixture was cooled to room temperature, and then water was added thereto, followed by extraction with ethyl acetate. The organic layer was washed with water and saturated brine successively, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane) to obtain the title compound (1.46 g). 1H-NMR (CDCl3) δ ppm: 0.91 (3H, t, J=7.4 Hz), 1.32 (3H, d, J=7.0 Hz), 1.55-1.80 (2H, m), 2.75-2.90 (1H, m), 3.84 (3H, s), 6.15-6.20 (1H, m), 6.77 (1H, dd, J=2.4, 8.8 Hz), 7.02 (1H, d, J=2.4 Hz), 7.19 (1H, d, J=8.8 Hz), 7.77 (1H, br s).

Source