反应详情

温度

70 °C

A solution of 5.79 g (27.5 mmol) of 2-(2-hydroxy-6-methoxyphenyl)ethyl acetate, 3.03 g (30.3 mmol) of 2-methylcrotonic acid and 3.26 g (16.9 mmol) of diphosphorus pentaoxide in 29.0 mL of methanesulfonic acid was heated and stirred at 70° C. for 75 minutes. 50 mL of toluene and 50 mL of water were added therein at room temperature and the mixture was stirred for 5 minutes, and then transferred to a separatory funnel and settled. The aqueous layer was separated and discarded and after the organic layer was washed with 25 mL of 5% sodium hydrogen carbonate aqueous solution and 25 mL of water sequentially, the solvent was evaporated to obtain 7.85 g of the crude title compound. This was purified by silica gel chromatography (developing solution composition: 10% ethyl acetate-hexane (volume ratio), Rf: 0.4), and 2.96 g of the title compound was obtained.

1. stirringat room temperature and the mixture was stirred for 5 minutes
2. customtransferred to a separatory funnel
3. customThe aqueous layer was separated
4. washafter the organic layer was washed with 25 mL of 5% sodium hydrogen carbonate aqueous solution and 25 mL of water sequentially
5. customthe solvent was evaporated
6. customto obtain 7.85 g of the crude title compound
7. customThis was purified by silica gel chromatography (developing solution composition: 10% ethyl acetate-hexane (volume ratio), Rf: 0.4)