Isopropanol → 4-(2-Nitro-1-propenyl)thiazole

Temperature

62.5 °C

In isopropyl alcohol (100 ml) was dissolved 4-formylthiazole (10.9 g), followed by the addition of potassium fluoride (280 mg) and nitromethane (14.46 g). The resulting mixture was stirred at 60 to 65° C. for 2 hours. The reaction mixture was then stirred overnight at room temperature. The solvent was distilled off under reduced pressure. The residue was dissolved in benzene (50 ml), followed by the addition of acetic anhydride (12.29 g) and 4-(dimethylamino)pyridine (588 g). The resulting mixture was heated under reflux for 2 hours. The solvent was distilled off under reduced pressure. Methylene chloride was added to the residue. The resulting mixture was washed with a saturated aqueous solution of sodium bicarbonate. The organic layer was then dried over anhydrous sodium sulfate and distilled under reduced pressure to remove the solvent. The residue was purified by chromatography on a silica gel column (hexane : ethyl acetate=1:1), whereby the title compound (8.73 g) was obtained as vividly yellow crystals.

1. stirringThe reaction mixture was then stirred overnight at room temperature
2. distillationThe solvent was distilled off under reduced pressure
3. dissolutionThe residue was dissolved in benzene (50 ml)
4. additionfollowed by the addition of acetic anhydride (12.29 g) and 4-(dimethylamino)pyridine (588 g)
5. temperatureThe resulting mixture was heated
6. temperatureunder reflux for 2 hours
7. distillationThe solvent was distilled off under reduced pressure
8. additionMethylene chloride was added to the residue
9. washThe resulting mixture was washed with a saturated aqueous solution of sodium bicarbonate
10. dry with materialThe organic layer was then dried over anhydrous sodium sulfate
11. distillationdistilled under reduced pressure
12. customto remove the solvent
13. customThe residue was purified by chromatography on a silica gel column (hexane : ethyl acetate=1:1), whereby the title compound (8.73 g)
14. customwas obtained as vividly yellow crystals

ORD record

ord-6b45f6f506cf454cbf03d5aa66c686b2

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06747023B1