反应详情

To a 100 mL round-bottomed flask was added 9-bromononanal (7.2 g, 32.5 mmol), methanol (30 mL) and trimethylorthoformate (4 mL, 36.5 mmol). A solution of 4 N hydrochloric acid in dioxane (0.2 mL, 0.8 mmol) was added and the resulting mixture was refluxed for 3 h. The reaction mixture was then cooled to room temperature and solid sodium bicarbonate (100 mg, 1.2 mmol) was added. The resulting mixture was concentrated to one-fourth its original volume under reduced pressure and then ethyl acetate (50 mL) was added. The organic layer was washed with water (2×40 mL), dried (MgSO4), filtered and concentrated under reduced pressure to afford the title intermediate (8.44 g, (97% yield)) as a liquid, which as used in the next step without further purification.

1. temperaturethe resulting mixture was refluxed for 3 h
2. concentrationThe resulting mixture was concentrated to one-fourth its original volume under reduced pressure
3. additionethyl acetate (50 mL) was added
4. washThe organic layer was washed with water (2×40 mL)
5. dry with materialdried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure