反应详情

1.50 g of p-toluenesulfonic acid and 2.9 ml of ethylene glycol were added to 17.8 g of 3-(5-benzyloxy-pentylidene)-7,7-ethylenedioxy-cis-bicyclo[3,3,0 ]octane (prepared as described in Preparation 3) in 300 ml of benzene, and the mixture was heated, with stirring, for 2.5 hours whilst removing water as an azeotropic mixture. Upon completion of the reaction, the reaction mixture was washed with water and dried over anhydrous sodium sulfate. The solvent was distilled off from the reaction mixture under reduced pressure, to give 18.20 g of the title compound as an oil. This mixture was used for the subsequent reaction of Preparation 5 without purification.

1. temperaturethe mixture was heated
2. customwhilst removing water as an azeotropic mixture
3. customUpon completion of the reaction
4. washthe reaction mixture was washed with water
5. dry with materialdried over anhydrous sodium sulfate
6. distillationThe solvent was distilled off from the reaction mixture under reduced pressure