反应详情

温度

-78 °C

To a solution of diisopropylamine (10.7 ml, 76.6 mmol) in anhydrous THF (100 ml) was added dropwise n-butyl lithium (1.61N, 47.6 ml, 76.6 mmol) at -78° C. under argon stream. After stirring the mixture at -78° C. for 30 minutes, ethyl 2-methylnonanoate (9.6028 g, 47.9 mmol) was added dropwise and the mixture was further stirred at -78° C. for 30 minutes. A solution of methyl iodide (5.5 ml, 88.3 mmol) in HMPA (2.5 ml, 14.4 mmol) was dropwise added and the mixture was stirred at -78° C. for 40 minutes, them at 0° C. for 40 minutes, and further at room temperature for 45 minutes. Saturated aqueous ammonium chloride solution (20 ml) was added and the reaction mixture was extracted with ethyl acetate (50 ml×4). The ethyl acetate layers were washed with water (50 ml) and with brine (50 ml), dried over anhydrous sodium sulfate, and concentrated. Distillation gave ethyl 2,2-dimethylnonanoate (9.6627 g, 94.1% yield, b.p.: 53°-65.5° C./0.22 mmHg) as colorless liquid. The structure of this product was confirmed by the following data.

1. stirringthe mixture was further stirred at -78° C. for 30 minutes
2. stirringthe mixture was stirred at -78° C. for 40 minutes
3. waitthem at 0° C. for 40 minutes
4. waitfurther at room temperature for 45 minutes
5. extractionthe reaction mixture was extracted with ethyl acetate (50 ml×4)
6. washThe ethyl acetate layers were washed with water (50 ml) and with brine (50 ml)
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationconcentrated
9. distillationDistillation