反应详情

5,6-dihydro-4H-cyclopenta[b]thiophene-2-carboxylic acid (commercially available: Matrix Chemicals) (0.5 g, 2.97 mmol) was suspended in dry diethyl ether (16 ml) and treated dropwise with a solution of lithium aluminium hydride (1.0 M solution in diethyl ether, 4.0 ml, 4.0 mol). The mixture was heated to reflux for 3 h and then cooled, treated dropwise with water (1.0 ml), then 1M HCl to dissolve the precipitated white solid. The product was extracted into diethyl ether (3×10 ml), dried over anhydrous magnesium sulphate and evaporated to afford 5,6-dihydro-4H-cyclopenta[b]thien-2-ylmethanol as a white solid (420 mg). This was dissolved in dichloromethane (60 ml) and treated with manganese dioxide (2.0 g). After stirring at room temperature overnight, the mixture was filtered through Kieselguhr and the solvent evaporated to afford the title compound as a yellow oil, (0.295 g, 64%).

1. temperatureThe mixture was heated
2. temperatureto reflux for 3 h
3. temperaturecooled
4. extractionThe product was extracted into diethyl ether (3×10 ml)
5. dry with materialdried over anhydrous magnesium sulphate
6. customevaporated