反应详情

The starting material is prepared as follows: To the suspension of 7.15 g of methyl sodium glycolate in 50 ml of dimethylsulfoxide and 25 ml of diemthylformamide, cooled to 0°, are added at once 9.5 g of methyl 4,4-diethoxy-crotonate and the mixture is stirred at room temperature for 3 hours. It is poured into water, washed with diethyl ether and the aqueous layer is acidified with cold N hydrochloric acid. It is extracted twice with diethyl ether, the extract dried, evaporated and the residue distilled, to yield the methyl 2-diethoxymethyl-4-oxo-tetrahydrofuran-3-carboxylate boiling at 123°-126°/0.5 mm Hg.

1. customThe starting material is prepared
2. temperaturecooled to 0°
3. washwashed with diethyl ether
4. extractionIt is extracted twice with diethyl ether
5. customthe extract dried
6. customevaporated
7. distillationthe residue distilled