Reacción #65929

Ecuación de reacción

3-Dipropylamino-5-methyloxycarbonylchroman

Sodium hydroxide

diphenylphosphoryl azid

→

title compound

3-Dipropylamino-5-aminochroman

Disolventes

Methanol

methanol

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturathe solution was refluxed with nitrogen overnight
2. 2
   OtroThe solution was evaporated to dryness, toluene (20 ml)
3. 3
   workup.ADDITIONwas added
4. 4
   Otroagain the solution was evaporated to dryness
5. 5
   workup.DISSOLUTIONThe residue was dissolved in toluene 20 ml
6. 6
   Temperaturathe solution was refluxed for 2 hours
7. 7
   Temperaturareflux
8. 8
   TemperaturaThe solution was cooled
9. 9
   Lavadowashed with water
10. 10
    Extracciónextracted with dilute HCl (aq.)
11. 11
    Extracciónextracted with toluene
12. 12
    SecadoThe toluene-phase was dried with sodium sulphate
13. 13
    Otroevaporated to dryness
14. 14
    workup.DISSOLUTIONThe residue was dissolved in ethanol containing 10% NaOH (20 ml)
15. 15
    Temperaturathe solution was refluxed overnight
16. 16
    TemperaturaThe solution was cooled
17. 17
    workup.ADDITIONdiluted with toluene
18. 18
    LavadoWashing with water
19. 19
    Otrodrying of the organic phase and evaporation to dryness

Procedimiento

3-Dipropylamino-5-methyloxycarbonylchroman (Example 2; 1.0 g, 3.4 mmol) was dissolved in methanol (20 ml). Sodium hydroxide (0.16 g, 4.1 mmol) in water (1.0 ml) was added and the solution was refluxed with nitrogen overnight. The solution was evaporated to dryness, toluene (20 ml) was added and again the solution was evaporated to dryness. The residue was dissolved in toluene 20 ml, diphenylphosphoryl azid (1.87 g, 6.8 mmol) was added and the solution was refluxed for 2 hours. Methanol (2.0 ml) was added and reflux was continued for 4 hours. The solution was cooled, washed with water and extracted with dilute HCl (aq.). The acidic water phase was neutralized NaOH (aq.) and extracted with toluene. The toluene-phase was dried with sodium sulphate and evaporated to dryness. The residue was dissolved in ethanol containing 10% NaOH (20 ml) and the solution was refluxed overnight. The solution was cooled and diluted with toluene. Washing with water, drying of the organic phase and evaporation to dryness afforded the title compound as an oil, which was converted to a dihydrochloride salt. Mp 173°-174° C.

Fuente