反应详情

To a stirred solution of 4.1 grams (0.024 mole) of dimethylmalonyl chloride and 3.8 grams (0.048 mole) of pyridine in 100 ml of dry toluene at 0° C., 4.7 grams (0.024 mole) of N-(2,5-dichlorophenylmethyl)hydroxylamine (Intermediate D) was added dropwise over 30 minutes, while the temperature was maintained at 0°±5° C. The reaction mixture was allowed to rise to ambient temperature and was stirred about 16 hours. A white solid was separated and washed with toluene. Filtrate and washings were combined, washed with water and saturated aqueous sodium chloride solution, and dried over sodium sulfate. Sodium sulfate was separated, and the liquid was concentrated under reduced pressure to a viscous liquid, and ultimately to a solid. Recrystallization from hexane-ethyl acetate yielded 2.7 grams of solid product; mp 78°-80° C. The nmr and ir spectra were consistent with the assigned structure.

1. temperaturewas maintained at 0°±5° C
2. customto rise to ambient temperature
3. customA white solid was separated
4. washwashed with toluene
5. washwashed with water and saturated aqueous sodium chloride solution
6. dry with materialdried over sodium sulfate
7. customSodium sulfate was separated
8. concentrationthe liquid was concentrated under reduced pressure to a viscous liquid
9. customRecrystallization from hexane-ethyl acetate