反应详情

KOtBu (0.673 g, 6 mmol) was dissolved in dry DMF (10 ml) with exclusion of oxygen. Phosphonoacetic acid triethyl ester (0.87 ml, 6 mmol) was then added to the mixture. After 20 min a solution of benzofuran-3(2H)-one (0.536 g, 4 mmol) in dry DMF (10 ml, argon atmosphere) was added to this mixture. The reaction mixture was stirred at room temperature for 1 h and thereafter poured on to ice (50 ml) for working up. The mixture obtained was extracted with diethyl ether (4×20 ml). The organic phase was washed with water (4×20 ml), dried with Na2SO4 and then concentrated. The product formed was purified by column chromatography [silica gel 60 (50 g); cyclohexane, ethyl acetate (4:1)] and obtained in a yield of 0.372 g (48%) as a yellowish oil.

1. customThe mixture obtained
2. extractionwas extracted with diethyl ether (4×20 ml)
3. washThe organic phase was washed with water (4×20 ml)
4. dry with materialdried with Na2SO4
5. concentrationconcentrated
6. customThe product formed
7. customwas purified by column chromatography [silica gel 60 (50 g); cyclohexane, ethyl acetate (4:1)]
8. customobtained in a yield of 0.372 g (48%) as a yellowish oil