Acetic Acid → 8-Allyl-7-methoxy-2-methoxymethyl-2-methyl-4-oxochromane

Participants

Reaction Steps

445 mg of 3′-allyl-2′-hydroxy-4′-methoxyacetophenone and 0.57 g of methoxyacetone were dissolved in 10 ml of toluene. Thereafter, 0.19 g of pyrrolidine and 0.19 ml of acetic acid were added to the reaction solution. Thereafter, the reaction solution was heated to reflux using Dean-Stark for 1 hour. Thereafter, the reaction solution was cooled to a room temperature. 1.14 g of methoxyacetone, 0.38 g of pyrrolidine, and 0.38 ml of acetic acid were added to the reaction solution, and the obtained mixture was further heated to reflux overnight. The reaction solution was cooled to a room temperature and then concentrated under a reduced pressure. The residue was diluted with ethyl acetate, and then successively washed with 2 N hydrochloric acid, a 1 N sodium hydroxide aqueous solution, water, and a saturated sodium chloride aqueous solution. The organic layer was dried over magnesium sulfate and then concentrated under a reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate), so as to obtain 194 mg of the subject compound.

Provenance & Evidence