反应详情

温度

7 °C

4-(5-Pentyl-1,3-dioxane-2-yl)cyclohexanecarboxylic acid methylester 28.2 g (94.5 mmol) was added in ethanol 100 ml, and cooled to 7° C., and 2N-sodium hydroxide 70 ml was added dropwise. The mixture was heated to room temperature, and stirred for one hour, and 2N-sodium hydroxide 70 ml was added dropwise. After st g the mixture father one hour at room temperature, 2N-sodium hydroxide 50 ml was added dropwise, and the mixture was stirred further one hour at room temperature. 6N-Hydrochloric acid 65 ml was added to the reactant, and the product was extracted with diethylether. The extract was washed with water, a saturated sodium bicarbonate aqueous solution and then water, and dried over magnesium sulfate, and the solvent was distilled off. The residue 27.3 g was purified by silica gel column chromatography (eluent: toluene/ethyl acetate=1/1), and recrystallized from a mixed solvent of heptane/ethanol =20/1 to obtain 4-(5-pentyl-1,3-dioxane-2-yl)cyclohexanecarboxylic acid 2.3 g (8.1 mmol). The yield was 8.6% from 4-(5-pentyl-1,3-dioxane-2-yl)cyclohexane carboxylic acid methylester.

1. temperatureThe mixture was heated to room temperature
2. stirringthe mixture was stirred further one hour at room temperature
3. extractionthe product was extracted with diethylether
4. washThe extract was washed with water
5. dry with materiala saturated sodium bicarbonate aqueous solution and then water, and dried over magnesium sulfate
6. distillationthe solvent was distilled off
7. customThe residue 27.3 g was purified by silica gel column chromatography (eluent: toluene/ethyl acetate=1/1)
8. customrecrystallized from a mixed solvent of heptane/ethanol =20/1