Reaktion #64132

Reaktionsgleichung

lithium

ammonium chloride

1,1-diethyl-3-(2,6-dimethyl-13-hydroxymethyl- 8alpha-ergolinyl)-urea

trimethylacetyl chloride

ammonia

→

1,1-Diethyl-3-(2,6,13-trimethyl-8alpha-ergolinyl)-urea

Lösungsmittel

water

chloroform

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONIce is added after 30 minutes
2. 2
   workup.STIRRINGit is stirred for another 30 minutes
3. 3
   Temperaturthe mixture is cooled in an ice bath
4. 4
   ExtraktionThe mother liquor is extracted with dichloromethane
5. 5
   Sonstigedried
6. 6
   Einengenconcentrated by evaporation
7. 7
   workup.DISSOLUTIONBoth fractions are dissolved together in 6 ml of tetrahydrofuran
8. 8
   Sonstigethe solution is instilled in 50 ml of condensed, anhydrous ammonia
9. 9
   workup.STIRRINGthe blue solution is stirred for 30 minutes at -40° C
10. 10
    Sonstigethe ammonia is evaporated
11. 11
    workup.ADDITIONit is diluted with 80 ml of water
12. 12
    workup.STIRRINGAfter 30 minutes of stirring in an ice bath
13. 13
    Trocknendried in a vacuum, yield 643 mg (94% of theory), [α]D =+3° (0.5% in chloroform)

Vorschrift

715 mg of 1,1-diethyl-3-(2,6-dimethyl-13-hydroxymethyl- 8alpha-ergolinyl)-urea (1.5 mmol) is dissolved in 10 ml of pyridine and mixed with 2 ml of trimethylacetyl chloride. Ice is added after 30 minutes of stirring at room temperature, it is stirred for another 30 minutes, made alkaline with ammonia and the mixture is cooled in an ice bath. The precipitated crystals are suctioned off, yield 785 mg, [α]D =-2° (0.5% in chloroform). The mother liquor is extracted with dichloromethane, dried and concentrated by evaporation. Both fractions are dissolved together in 6 ml of tetrahydrofuran and the solution is instilled in 50 ml of condensed, anhydrous ammonia. Then, it is mixed with 160 mg of lithium and the blue solution is stirred for 30 minutes at -40° C. Solid ammonium chloride, until decolorization, and 5 ml water are added in succession, the ammonia is evaporated and it is diluted with 80 ml of water. After 30 minutes of stirring in an ice bath, the precipitated crystals are suctioned off and dried in a vacuum, yield 643 mg (94% of theory), [α]D =+3° (0.5% in chloroform).

Quelle