反应详情

To a suspension of magnesium chloride (1.33 g) in dichloromethane (40 mL) was added 1-tert-butyl 7-ethyl 2-acetylheptanedioate (4.0 g) at ambient temperature under N2. To this mixture was added dropwise pyridine (2.26 mL) in an ice-water bath. Then the mixture was stirred at ambient temperature for 40 minutes. To the reaction mixture was added a solution of 3-cyanobenzoyl chloride (3.01 g) in dichloromethane (6 mL) dropwise over 2 minutes. The reaction mixture was stirred at ambient temperature for 2 hours. To the mixture was added 1N hydrogen chloride and ethyl acetate in an ice-water bath. The organic layer was washed with 1N hydrogen chloride, water, and brine, dried over magnesium sulfate, and evaporated in vacuo to give a solid. The residue was purified by flash silica gel chromatography (silica gel, 300 mL) eluting with hexane-ethyl acetate=10-1, 8-1, 5-1, and 3-1 to give 1-tert-butyl 7-ethyl 2-acetyl-2-(3-cyanobenzoyl)heptanedioate (4.23 g, 72.9%) as colorless oil.

1. stirringThe reaction mixture was stirred at ambient temperature for 2 hours
2. washThe organic layer was washed with 1N hydrogen chloride, water, and brine
3. dry with materialdried over magnesium sulfate
4. customevaporated in vacuo
5. customto give a solid
6. customThe residue was purified by flash silica gel chromatography (silica gel, 300 mL)
7. washeluting with hexane-ethyl acetate=10-1, 8-1, 5-1, and 3-1