反应详情

To a solution of 11,11-dimethyl-spiro[5.5]undec-7-en-2-ol (320 mg) obtained in Step 4 in chloroform (10 mL) was added 1,1,1-tris(acetyloxy)-1,1-dihydro-1,2-benziodoxol-3-(1H)-on e (Dess-Martin periodinane; 735 mg) under ice-cooling, followed by stirring the reaction mixture under ice-cooling for 3 hours. Then, after addition of aqueous sodium sulfite solution to the reaction mixture, chloroform was evaporated off in vacuo. To the residue was added aqueous sodium bicarbonate solution, followed by extraction with ethyl acetate. The organic layer was washed with water, dried and concentrated. The residue was purified by column chromatography on silica gel (hexane:ethyl acetate (volume ratio)=20:1) to give 11,11-dimethyl-spiro[5.5]undec-7-en-2-one (290 mg).

1. temperaturecooling
2. temperaturecooling for 3 hours
3. customwas evaporated off in vacuo
4. additionTo the residue was added aqueous sodium bicarbonate solution
5. extractionfollowed by extraction with ethyl acetate
6. washThe organic layer was washed with water
7. customdried
8. concentrationconcentrated
9. customThe residue was purified by column chromatography on silica gel (hexane:ethyl acetate (volume ratio)=20:1)