Acetic Acid → Methyl 2-acetyl-3,5-diallyloxyphenylacetate

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Reaction Conditions

Reaction Steps

Methyl 3,5-diallyloxyphenylacetate (40 g, 0.14 mol) obtained in Example 5, Step 1 was dissolved in trifluoroacetic acid (0.15 L). After the solution was cooled to 4° C., acetic acid (9.5 mL, 0.17 mol) and trifluoroacetic anhydride (40 mL, 0.28 mol) were added thereto, followed by stirring at 4° C. for 3.5 hours. The reaction mixture was gradually added to a saturated aqueous solution of sodium hydrogencarbonate for neutralization, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (ethyl acetate/hexane=1/20-1/6) to obtain methyl 2-acetyl-3,5-diallyloxyphenylacetate (30 g, 65%). 1H-NMR (CDCl3, 300 MHz) δ (ppm): 6.43 (d, J=2.2 Hz, 1H), 6.37 (d, J=2.2 Hz, 1H), 6.07-5.98 (m, 2H), 5.44-5.27 (m, 4H), 4.57-4.52 (m, 4H), 3.69 (s, 2H), 3.68 (s, 3H), 2.53 (s, 3H)

Provenance & Evidence