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

Participants

Reaction Steps

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%).

Provenance & Evidence