反应详情

Triethylamine (11.7 mL, 84.3 mmol) was added dropwise to a suspension of potassium ethyl malonate (13.4 g, 78.5 mmol) in acetonitrile (80 mL) at 10° C., followed by portionwise addition of anhydrous magnesium chloride (9.12 g, 95.8 mmol). The reaction mixture was warmed to room temperature and stirred for 2.5 h. The resulting white slurry was cooled to 0° C. and furan-2-carbonyl chloride (5.0 g, 38.3 mmol) in acetonitrile (20 mL) was added dropwise over a period of 20 min. The mixture was allowed to stir at ambient temperature overnight. The solvent was evaporated in vacuo and the residue was azeotroped with toluene (10 mL) then dissolved in toluene, cooled to between 0 and 5° C. and acidified with 13% aqueous hydrochloric acid (50 mL). After stirring for 15 min the aqueous phase was separated and the organic phase was washed with 13% aqueous hydrochloric acid (2×50 mL) followed by water (2×25 mL) and concentrated in vacuo to afford the crude compound. Purification by flash column chromatography over silica gel (100-200 mesh) using 5% ethyl acetate in petroleum ether as eluent afforded ethyl 3-(2-furyl)-3-oxo-propanoate (5.01 g, 72%) as a pale yellow liquid.

1. temperatureThe resulting white slurry was cooled to 0° C.
2. stirringto stir at ambient temperature overnight
3. customThe solvent was evaporated in vacuo
4. customthe residue was azeotroped with toluene (10 mL)
5. dissolutionthen dissolved in toluene
6. temperaturecooled to between 0 and 5° C.
7. stirringAfter stirring for 15 min the aqueous phase
8. customwas separated
9. washthe organic phase was washed with 13% aqueous hydrochloric acid (2×50 mL)
10. concentrationconcentrated in vacuo
11. customto afford the crude compound
12. customPurification by flash column chromatography over silica gel (100-200 mesh)