反应详情

A mixture of 2-oxobutyl benzoate (5 g, 26 mmol), 1,3-propanediol (5.94 g, 78 mmol), triethyl orthoformate (3.85 g, 26 mmol) and p-toluenesulfonic acid monohydrate (448 mg, 2.36 mmol) was stirred at room temperature for 3 hours and 30 minutes. To the reaction mixture, ethyl acetate and diethyl ether were added and the mixture was washed with water and a saturated saline solution. The organic layer was dried over sodium sulfate and filtrated. The filtrate was concentrated under reduced pressure. The residue was dissolved in heptane/ethyl acetate (12/1) and subjected to NH silica gel column chromatography (elution solvent: n-heptane/ethyl acetate=12/1) to obtain the title compound (4.33 g, 65.5%) as a colorless viscous oil.

1. washthe mixture was washed with water
2. dry with materialThe organic layer was dried over sodium sulfate
3. filtrationfiltrated
4. concentrationThe filtrate was concentrated under reduced pressure
5. dissolutionThe residue was dissolved in heptane/ethyl acetate (12/1)
6. washsubjected to NH silica gel column chromatography (elution solvent: n-heptane/ethyl acetate=12/1)