Reaktion #1927609

Reaktionsgleichung

hydrogen

hydrochloric acid

7-(2-Azidoethyl)thioimidazo[5,1-b]thiazole

THF

→

7-(2-Formylaminoethyl)thioimidazo[5,1-b]thiazole

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe catalyst was removed by filtration on Celite
2. 2
   Waschenwas then washed with water
3. 3
   EinengenThe filtrate was concentrated under the reduced pressure until the volume
4. 4
   workup.ADDITIONDichloromethane (20 ml) was added
5. 5
   workup.ADDITIONthe mixture was adjusted to pH 7.0 by the addition of an aqueous sodium hydrogencarbonate solution
6. 6
   workup.STIRRINGFormic acid (0.90 ml) and 0.50 ml of acetic anhydride, which had been stirred at 50° C. for 5 min
7. 7
   workup.ADDITIONwere added
8. 8
   workup.STIRRINGThe mixture was stirred at that temperature for 20 min
9. 9
   Temperaturwhile maintaining the pH value at about 7.0
10. 10
    workup.ADDITIONThe reaction solution was adjusted to pH 8.3 by the addition of an aqueous sodium hydrogencarbonate solution
11. 11
    Extraktionwas then extracted with dichloromethane three times
12. 12
    TrocknenThe organic layer was dried over anhydrous magnesium sulfate
13. 13
    SonstigeThe solvent was then removed by distillation
14. 14
    Sonstigethe residue was purified by column chromatography on silica gel (dichloromethane:methanol=20:1)
15. 15
    Sonstigeto prepare 250 mg of 7-(2-formylaminoethyl)thioimidazo[5,1-b]thiazole

Vorschrift

7-(2-Azidoethyl)thioimidazo[5,1-b]thiazole (397 mg) was dissolved in a mixed solvent composed of 10 ml of THF and 10 ml of water. A 1 N aqueous hydrochloric acid solution (5.3 ml) and 200 mg of 10% Pd-C were added to the solution. The air in the reaction vessel was replaced by hydrogen, and the contents of the reaction vessel were stirred at room temperature for 6 hr. The catalyst was removed by filtration on Celite, and was then washed with water. The filtrate was concentrated under the reduced pressure until the volume was substantially halved. Dichloromethane (20 ml) was added, and the mixture was adjusted to pH 7.0 by the addition of an aqueous sodium hydrogencarbonate solution. Formic acid (0.90 ml) and 0.50 ml of acetic anhydride, which had been stirred at 50° C. for 5 min, were added thereto under ice cooling. The mixture was stirred at that temperature for 20 min while maintaining the pH value at about 7.0. The reaction solution was adjusted to pH 8.3 by the addition of an aqueous sodium hydrogencarbonate solution, and was then extracted with dichloromethane three times. The organic layer was dried over anhydrous magnesium sulfate. The solvent was then removed by distillation, and the residue was purified by column chromatography on silica gel (dichloromethane:methanol=20:1) to prepare 250 mg of 7-(2-formylaminoethyl)thioimidazo[5,1-b]thiazole.

Quelle