Reacción #45908

Ecuación de reacción

tert-butyl (3S)-3-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate

trifluoroacetic acid

triethylamine

diphenylphosphorylazide

tert-Butanol

→

compound

Rendimiento 60.0%

tert-Butyl {(3S)-3-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidin-3-yl}carbamate

Rendimiento 60.0%

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction liquid
2. 2
   Concentraciónwas concentrated under reduced pressure
3. 3
   workup.DISSOLUTIONdissolved in chloroform
4. 4
   Lavadowashed with saturated brine (60 ml)
5. 5
   SecadoAfter drying over anhydrous sodium sulfate and concentration under reduced pressure
6. 6
   workup.DISSOLUTIONthe resulting residue was dissolved in toluene (20 ml)
7. 7
   workup.STIRRINGby stirring at room temperature for 30 minutes
8. 8
   workup.STIRRINGby stirring in an oil bath at 125° C. for 3 hours
9. 9
   workup.STIRRINGby stirring in an oil bath at 100° C. for 11 hours
10. 10
    OtroThe reaction liquid
11. 11
    Concentraciónwas concentrated under reduced pressure
12. 12
    workup.DISSOLUTIONthe residue was dissolved in ethyl acetate
13. 13
    Lavadowashed with saturated brine
14. 14
    SecadoAfter drying over anhydrous sodium sulfate and concentration
15. 15
    Otrothe resulting residue was purified by silica gel column chromatography (eluent, n-hexane:ethyl acetate=2:1→1:4, v/v)

Procedimiento

With cooling with ice, trifluoroacetic acid (7 ml) was added to a dichloromethane (14 ml) solution of tert-butyl (3S)-3-methyl-5-oxo-1-[(1R)-1-phenylethyl]pyrrolidine-3-carboxylate (I-342) (800 mg, 2.64 mmol), followed by stirring at room temperature for 13 hours. The reaction liquid was concentrated under reduced pressure, dissolved in chloroform, washed with saturated brine (60 ml). After drying over anhydrous sodium sulfate and concentration under reduced pressure, the resulting residue was dissolved in toluene (20 ml), then triethylamine (735 μl, 5.27 mmol) and diphenylphosphorylazide (739 μl, 3.43 mmol) were added, followed by stirring at room temperature for 30 minutes, then by stirring in an oil bath at 125° C. for 3 hours. tert-Butanol (20 ml) was added to the reaction liquid, followed by stirring in an oil bath at 100° C. for 11 hours. The reaction liquid was concentrated under reduced pressure, the residue was dissolved in ethyl acetate, washed with saturated brine. After drying over anhydrous sodium sulfate and concentration, the resulting residue was purified by silica gel column chromatography (eluent, n-hexane:ethyl acetate=2:1→1:4, v/v) to obtain the entitled compound (500 mg, 60%) as a colorless oily substance.

Fuente