反应详情

20 mL of concentrated hydrochloric acid was added to a solution of 1-cyano-1-(trans-4-methoxycyclohexyl)-4-decanol (49) (5.1 g, 17.4 mmol) obtained in the third step dissolved in 200 mL of 1,3-dioxane, and refluxed under heating for 20 hours. The reaction mixture was cooled to room temperature and then put in 100 mL of water, and then extracted with 100 mL of ethyl acetate. The resulting organic layer was washed with water (100 mL×2) and dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The resulting residue was purified by column chromatography (developing solvent: heptane/ethyl acetate=20/1, column packing: silica gel) and then recrystallized from heptane to obtain 3-(trans-4-methoxycyclohexyl)-6-hexyl-tetrahydro-2-pyranone (Compound No. 25) (2.1 g, 6.9 mmol). The resulting compound was in the form of a colorless liquid, and the yield based on the compound (49) was 40%.

1. customobtained in the third step
2. temperaturerefluxed
3. temperatureunder heating for 20 hours
4. extractionextracted with 100 mL of ethyl acetate
5. washThe resulting organic layer was washed with water (100 mL×2)
6. dry with materialdried over anhydrous sodium sulfate
7. distillationthe solvent was distilled off under reduced pressure
8. customThe resulting residue was purified by column chromatography (developing solvent: heptane/ethyl acetate=20/1, column packing: silica gel)
9. customrecrystallized from heptane