反应详情

温度

80 °C

In a 300 ml three neck flask, 5.2 g (31 mmol) of ethyl p-hydroxybenzoate, 4.7 g (34 mmol) of potassium carbonate anhydride, and 7.8 g (31 mmol) of the 3-[(4-bromobutoxy)methyl]-3-ethyloxetane were dissolved in 50 ml of dimethylformamide. After the solution remained turbid was heated to a temperature of 80° C. and stirred for 4 hours, the solvent was completely distilled out in a vacuum. To the resulting yellow oily substance were added 15 ml of a 7% sodium hydroxide aqueous solution and 15 ml of methanol. The mixture was refluxed for two and half hours. 1 N (normality) of hydrochloric acid was added to the mixture such that the pH is adjusted to about 3. The resulting white precipitate was filtered and dried in a vacuum thereby obtaining 8.6 g (28 mmol) of 4-[7-(3-ethyl-3-oxetanyl)-1,6-dioxaheptyl]benzoic acid (yield: 89%, identified with 1H-NMR). The resulting compound was no more purified and used in the following reaction.

1. distillationthe solvent was completely distilled out in a vacuum
2. additionTo the resulting yellow oily substance were added 15 ml of a 7% sodium hydroxide aqueous solution and 15 ml of methanol
3. temperatureThe mixture was refluxed for two and half hours
4. addition1 N (normality) of hydrochloric acid was added to the mixture such that the pH
5. filtrationThe resulting white precipitate was filtered
6. customdried in a vacuum