反应详情

To 2 g (8 mmol) of 2-tridecyl-2,3-dihydrofuran an 1.1 g (8.8 mmol) of 2-bromo-ethanol in 50 ml of carbon tetrachloride were added 20 mg (0.1 mmol) of dry p-toluene-sulphonic acid. After stirring overnight at room temperature, the solvent was evacuated under reduced pressure. The residue was diluted with a aqueous solution of sodium carbonate and extracted with diethyl ether. The organic phase was washed with water and then dryed on anhydrous magnesium sulphate. The solvent was removed by evaporation and the residue was chromatographed on silica gel using 10% by volume diethyl ether in petroleum ether as eluent. This method allowed the recovery, as oils, of first the trans title compound (896 mg) then a mixture of both cis and trans isomers (419 mg) and, finally, the cis isomer (340 mg) as confirmed by their spectral data: NMR (250 MHz, CDCl3, TMS*) δ ##STR25##

1. customthe solvent was evacuated under reduced pressure
2. additionThe residue was diluted with a aqueous solution of sodium carbonate
3. extractionextracted with diethyl ether
4. washThe organic phase was washed with water
5. customThe solvent was removed by evaporation
6. customthe residue was chromatographed on silica gel using 10% by volume diethyl ether in petroleum ether as eluent
7. additionas oils, of first the trans title compound (896 mg) then a mixture of both cis and trans isomers (419 mg)