Reacción #2267058

Ecuación de reacción

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

Disolventes

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe mixture was heated
2. 2
   Temperaturato reflux
3. 3
   Temperaturaat reflux over night
4. 4
   TemperaturaAs the mixture warmed the cream suspension
5. 5
   workup.DISSOLUTIONgradually dissolved
6. 6
   TemperaturaJust before refluxing
7. 7
   Otroformed
8. 8
   Filtraciónfiltered
9. 9
   Lavadothe residue was washed well with ethanol
10. 10
    ConcentraciónThe resulting filtrate was concentrated to dryness
11. 11
    Otroto give an off-white solid
12. 12
    Lavadowashed with 1) water (800 mL) and 2) brine (1 L)
13. 13
    SecadoThe filtrate was dried (MgSO4)
14. 14
    Concentraciónconcentrated to dryness
15. 15
    OtroAn off-white solid was obtained
16. 16
    Otrothat was recrystallised
17. 17
    LavadoThe filtered material was washed well with acetonitrile
18. 18
    Otrodried (Vac/40° C.)

Procedimiento

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%.

Fuente