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

2-Acetylfuran (5.1 g, 46.0 mmol) was dissolved in a mixed solvent of dichloromethane (50 mL) and methanol (50 mL), and tetra(n-butyl)ammonium bromide (22.3 g, 46.0 mmol) was added thereto, followed by stirring at room temperature for 1 hour. The reaction mixture was concentrated under reduced pressure, water was added to the resulting residue, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, and then the solvent was distilled away under reduced pressure. The resulting residue was dissolved in acetonitrile (60 mL), thiourea (3.5 g, 46.0 mmol) was added thereto, followed by stirring at room temperature for 30 minutes. The precipitated solid was collected by filtration, and the resulting solid was dissolved in a mixed solvent of a saturated aqueous solution of sodium hydrogencarbonate and ethyl acetate, and subjected to liquid-liquid separation. The organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, and then the solvent was distilled away under reduced pressure. The resulting residue was purified through silica gel column chromatography (hexane:ethyl acetate=3:1) to afford 2-amino-4-(2-furyl)thiazole (1.53 g, 20%).

1. additionwas added
2. concentrationThe reaction mixture was concentrated under reduced pressure, water
3. additionwas added to the resulting residue
4. extractionfollowed by extraction with ethyl acetate
5. washThe organic layer was washed with a saturated aqueous solution of sodium chloride
6. dry with materialdried over anhydrous magnesium sulfate
7. distillationthe solvent was distilled away under reduced pressure
8. dissolutionThe resulting residue was dissolved in acetonitrile (60 mL)
9. stirringby stirring at room temperature for 30 minutes
10. filtrationThe precipitated solid was collected by filtration
11. dissolutionthe resulting solid was dissolved in a mixed solvent of a saturated aqueous solution of sodium hydrogencarbonate and ethyl acetate
12. customsubjected to liquid-liquid separation
13. washThe organic layer was washed with a saturated aqueous solution of sodium chloride
14. dry with materialdried over anhydrous magnesium sulfate
15. distillationthe solvent was distilled away under reduced pressure
16. customThe resulting residue was purified through silica gel column chromatography (hexane:ethyl acetate=3:1)

ORD record

ord-2d54ea44408d403a885482f00456307c

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08889718B2