Reaktion #2267058

Reaktionsgleichung

Sodium hydroxide

2-methylpentyl methanesulphonate

ethanol

2-mercapto-1,3,4-thiadiazole-5-amine

→

required product

2-(2-Methylpentylthio)-1,3,4-thiadiazole-5-amine

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was heated
2. 2
   Temperaturto reflux
3. 3
   Temperaturat reflux over night
4. 4
   TemperaturAs the mixture warmed the cream suspension
5. 5
   workup.DISSOLUTIONgradually dissolved
6. 6
   TemperaturJust before refluxing
7. 7
   Sonstigeformed
8. 8
   Filtrationfiltered
9. 9
   Waschenthe residue was washed well with ethanol
10. 10
    EinengenThe resulting filtrate was concentrated to dryness
11. 11
    Sonstigeto give an off-white solid
12. 12
    Waschenwashed with 1) water (800 mL) and 2) brine (1 L)
13. 13
    TrocknenThe filtrate was dried (MgSO4)
14. 14
    Einengenconcentrated to dryness
15. 15
    SonstigeAn off-white solid was obtained
16. 16
    Sonstigethat was recrystallised
17. 17
    WaschenThe filtered material was washed well with acetonitrile
18. 18
    Sonstigedried (Vac/40° C.)

Vorschrift

A three-necked 3-L round bottom flask was charged with 2-methylpentyl methanesulphonate (90 g, 0.5 mol), ethanol (1.5 L) and 2-mercapto-1,3,4-thiadiazole-5-amine (66.5 g, 0.5 mol). Sodium hydroxide (20 g, 0.5 mol) was added to the stirred suspension. The mixture was heated to reflux and held at reflux over night. As the mixture warmed the cream suspension gradually dissolved. Just before refluxing began a cloudy precipitate formed. The reaction mixture was cooled to room temperature, filtered, and the residue was washed well with ethanol. The resulting filtrate was concentrated to dryness to give an off-white solid that was dissolved in ethyl acetate (1.2 L) and washed with 1) water (800 mL) and 2) brine (1 L). The filtrate was dried (MgSO4) and concentrated to dryness. An off-white solid was obtained that was recrystallised from boiling acetonitrile (150 mL). The filtered material was washed well with acetonitrile and dried (Vac/40° C.). The required product was obtained as a white solid wt 83 g; 76.5%.

Quelle