2-Acetylfuran → 4-(Furan-2-yl)-1,3-thiazol-2-amine

2-Acetylfuran (5.10 g, 46.0 mmol) was dissolved in a mixed solvent of dichloromethane (50 mL) and methanol (50 mL), and N,N,N,N-tetra-n-butylammonium tribromide (22.3 g, 46.0 mmol) added thereto, then the solution was stirred at room temperature for 1 hour. The reaction mixture was concentrated under reduced pressure, and water was added to the resulting residue, then the mixture was extracted with ethyl acetate. The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The solvent was then evaporated under reduced pressure. The resulting residue was dissolved in acetonitrile (60 mL), and thiourea (3.5 g, 46.0 mmol) added thereto, then the solution was stirred at room temperature for 30 minutes. The precipitated solid was collected by filtration, and to the resulting solid was added saturated sodium bicarbonate aqueous solution and ethyl acetate added, then the mixture was extracted. The organic layer was washed with brine and dried over anhydrous magnesium sulfate. The solvent was then evaporated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=3:1) to give 2-amino-4-(2-furyl)thiazole (1.53 g, 20%).

1. additionadded
2. concentrationThe reaction mixture was concentrated under reduced pressure, and water
3. additionwas added to the resulting residue
4. extractionthe mixture was extracted with ethyl acetate
5. washThe organic layer was washed with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. customThe solvent was then evaporated under reduced pressure
8. dissolutionThe resulting residue was dissolved in acetonitrile (60 mL)
9. stirringthe solution was stirred at room temperature for 30 minutes
10. filtrationThe precipitated solid was collected by filtration
11. additionto the resulting solid was added saturated sodium bicarbonate aqueous solution and ethyl acetate
12. additionadded
13. extractionthe mixture was extracted
14. washThe organic layer was washed with brine
15. dry with materialdried over anhydrous magnesium sulfate
16. customThe solvent was then evaporated under reduced pressure
17. customThe resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=3:1)

ORD record

ord-3c8d6a9e291d4478bc61e89d6e511efb

Source dataset

uspto-grants-2011_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07928098B2