反应详情

Ethylene glycol (2.18 ml) and p-toluenesulfonic acid (0.74 g) is added to a solution of 2-brom-3-methyl-5-formylthiophene (4.0 g) in toluene (98 ml) in a Dean-Stark apparatus. After 18 hours at reflux, the reaction is quenched with water. The organic phase is separated and the aqueous phase is extracted three times with ethyl acetate. The combined organic phases are dried over Na2SO4 and concentrated in vacuo. The crude product is purified on a semi-preparative HPLC to yield 2-(5-bromo-4-methyl-thiophen-2-yl)-[1,3]dioxolane (4.04 g) as a yellow oil. MS (HPLC/MS): 250 (MH+). Retention time: 4.02 min.

1. temperatureAfter 18 hours at reflux
2. customthe reaction is quenched with water
3. customThe organic phase is separated
4. extractionthe aqueous phase is extracted three times with ethyl acetate
5. dry with materialThe combined organic phases are dried over Na2SO4
6. concentrationconcentrated in vacuo
7. customThe crude product is purified on a semi-preparative HPLC