Methyl iodide → 2-Methoxy-2,4,6-cycloheptatrien-1-one

To the mixture of 20 g (0.16 mol) of tropolone (2-hydroxy-2,4,6-cycloheptatrienone), 68 g (0.48 mol) of anhydrous potassium carbonate, 6.1 g (0.016 mol) of dicyclohexyl-18-crown-6 and 750 ml of acetonitrile were added 117 g (0.8 mol) of methyl iodide with stirring. After stirred under reflux for 10 hours, the reaction mixture was filtered. The filtrate was concentrated under reduced pressure, and the residue was dissolved in dichloromethane. After washing with 13.8% aqueous solution of potassium carbonate and water. After drying with magnesium sulfate anhydrous, dichloromethane was evaporated under reduced pressure, and the residue was subjected to purification by means of silica gel column chromatography. Elution was carried out by using ethyl acetate and the solvent was evaporated under reduced pressure to give 20 g of 2-methoxytropone (2-methoxy-2,4,6-cycloheptatrienone) (yield: 92%).

1. stirringAfter stirred
2. temperatureunder reflux for 10 hours
3. filtrationthe reaction mixture was filtered
4. concentrationThe filtrate was concentrated under reduced pressure
5. dissolutionthe residue was dissolved in dichloromethane
6. washAfter washing with 13.8% aqueous solution of potassium carbonate and water
7. dry with materialAfter drying with magnesium sulfate anhydrous, dichloromethane
8. customwas evaporated under reduced pressure
9. customthe residue was subjected to purification by means of silica gel column chromatography
10. washElution
11. customthe solvent was evaporated under reduced pressure

ORD record

ord-361af9dd242f4effbae5e361bbadc82d

Source dataset

uspto-grants-1991_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05013736