反应详情

L-prolinal diethyl acetal hydrochloride is dissolved, together with 4-(p-methoxyphenyl)butyryl chloride (686 mg, 4.02 mmol) prepared in the same manner as described in Example 5, in methylene chloride (12 ml) and triethylamine (1.7 ml, 12.2 mmol) is added dropwise thereto under ice-cooling and agitation. After the dropwise addition, stirring is further continued for 30 minutes under cooling, and then for one hour at room temperature. Ether (40 ml) is added to the reaction mixture, and the ethereal layer is separated, washed with a saturated aqueous solution of sodium hydrogen carbonate and a saturated aqueous solution of edible salt, dried over sodium sulfate and filtered. The filtrate is concentrated to dryness under reduced pressure. The residue is purified by column chromatography on silica gel (n-hexane-ethyl acetate, 2:1) to give 805 mg (58%) of the title compound as a pale yellow syrup.

1. customprepared in the same manner
2. temperatureunder ice-cooling
3. additionAfter the dropwise addition
4. temperatureunder cooling
5. waitfor one hour at room temperature
6. customthe ethereal layer is separated
7. washwashed with a saturated aqueous solution of sodium hydrogen carbonate
8. dry with materiala saturated aqueous solution of edible salt, dried over sodium sulfate
9. filtrationfiltered
10. concentrationThe filtrate is concentrated to dryness under reduced pressure
11. customThe residue is purified by column chromatography on silica gel (n-hexane-ethyl acetate, 2:1)