反应详情

24.5 ml (24.5 mmol) of 1.0 M diethyl zinc/hexane solution was added to 30 ml of dichloromethane, and then a solution of 1.89 ml (24.5 mmol) of trifluoroacetic acid in 10 ml of dichloromethane was added with stirring under ice-cooling. The reaction solution was stirred for 20 minutes at the same temperature, then a solution of 1.97 ml (24.5 mmol) of diiodomethane in 10 ml of dichloromethane was added and stirred for 20 minutes, and 1.40 g (6.13 mmol) of a solution of diethyl 4-methyleneheptanedicarboxylate (compound described in J.A.C.S. 107, 13, 3981-3997 (1985)) in 10 ml of dichloromethane was further added. After the reaction solution was stirred for 6 hours at room temperature, ice water was added to the reaction solution and the mixture was extracted with ethyl acetate. The organic layer was washed with water and dried over anhydrous magnesium sulfate, followed by concentration under reduced pressure. The residue was subjected to silica gel column chromatography (solvent; hexane:ethyl acetate=5:1) to give 1.48 g of the title compound as a brown oil (yield: 99%).

1. temperaturecooling
2. stirringThe reaction solution was stirred for 20 minutes at the same temperature
3. stirringstirred for 20 minutes
4. stirringAfter the reaction solution was stirred for 6 hours at room temperature
5. extractionthe mixture was extracted with ethyl acetate
6. washThe organic layer was washed with water
7. dry with materialdried over anhydrous magnesium sulfate
8. concentrationfollowed by concentration under reduced pressure