Reaktion #1922796

Reaktionsgleichung

sodium cyanoborohydride

2-amino-oxo-4,5,6,7-tetrahydrobenzothiazole

propylamine hydrochloride

propylamine

→

(±)2-amino-6-propylamino-4,5,6,7-tetrahydrobenzothiazole

Lösungsmittel

water

hydrochloric acid

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeSolvents were removed by evaporation
2. 2
   workup.STIRRINGthe yellow residue was stirred with ethanol
3. 3
   Sonstigethe solid was removed by filtration
4. 4
   Sonstigethe precipitate was again removed by filtration
5. 5
   Sonstigeevaporated with ethanol
6. 6
   Sonstigeto remove propylamine
7. 7
   workup.DISSOLUTIONThe residue was dissolved in hot ethanol
8. 8
   Sonstigeresulting crystals
9. 9
   Sonstigewere collected
10. 10
    Sonstigedried
11. 11
    SonstigeReaction product

Vorschrift

3.0 g of propylamine hydrochloride was dissolved in 60 mL of methanol and 2.2 g of 2-amino-oxo-4,5,6,7-tetrahydrobenzothiazole was added. 1.1 mL of propylamine was poured into the mixture to set pH within the range 6.5-7.0. Then 0.7 g of sodium cyanoborohydride was added and the reaction mixture was stirred for 70 hours under nitrogen atmosphere and at ambient temperature. The reaction mixture was diluted with 50 mL of water and 10 mL of conc. hydrochloric acid. Solvents were removed by evaporation, the yellow residue was stirred with ethanol and the solid was removed by filtration. The filtrate was made alkaline with potassium hydroxide solution and the precipitate was again removed by filtration. Filtrate was several times evaporated with ethanol to remove propylamine. The residue was dissolved in hot ethanol and resulting crystals were collected and dried. Reaction product was characterised by NMR spectra.

Quelle