反应详情

To a solution of Meldrum's acid (14.4 g, 0.10 mol) and pyridine (15.8 g, 0.20 mol) in dichloromethane (100 mL) was added dropwise at 0° C., taking 10 minutes, a solution of phthalimidoacetyl chloride (24.6 g,. 0.11 mol) in dichloromethane (50 mL). The mixture was stirred for 30 minutes at the same temperature and for 30 minutes at room temperature. To the reaction mixture was added 1N HCl (200 mL), then insoluble material was filtered off. The aqueous layer was separated, and the organic layer was washed with water, dried over magnesium sulfate and subjected to filtration. The filtrate was concentrated under reduced pressure. The concentrate was suspended in methanol (200 mL), which was refluxed for 1.5 hour. The reaction mixture was left standing for cooling. Crystalline precipitate was collected by filtration and washed with methanol to give the object compound (18.4 g, 70%), m.p.139°-140° C.

1. filtrationinsoluble material was filtered off
2. customThe aqueous layer was separated
3. washthe organic layer was washed with water
4. dry with materialdried over magnesium sulfate
5. filtrationsubjected to filtration
6. concentrationThe filtrate was concentrated under reduced pressure
7. temperaturewhich was refluxed for 1.5 hour
8. waitThe reaction mixture was left
9. temperaturefor cooling
10. filtrationCrystalline precipitate was collected by filtration
11. washwashed with methanol