反应详情

A mixture comprising 2.0 g of 4-tert-butylbenzyl cyanide, 2.34 g of 2-trifluoromethylbenzoyl chloride and 8 ml of dimethylformamide, was dropwise added to a mixture comprising 0.83 g of 68% sodium hydride and 13 ml of dimethylformamide while maintaining the temperature at a level of from 40 to 500C. After completion of the dropwise addition, the reaction was carried out for 30 minutes at room temperature. The reaction mixture was cooled with ice, and a mixture comprising 2.1 g of ethyl chlorothioformate and 1.2 ml of dimethylformamide, was dropwise added. After completion of the dropwise addition, the reaction was carried out for 30 minutes under cooling with ice. The reaction mixture was poured into ice water and extracted with methylene chloride and then washed with water. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate/n-hexane=1/9) to obtain 3.2 g of the desired product (isomer ratio 35:65) having a melting point of 62 to 64° C. The HPLC conditions for the analysis of this product were the same as in Preparation Example 1. Further, the NMR spectrum data of the respective geometrical isomers are as follows.

1. additionAfter completion of the dropwise addition
2. temperatureThe reaction mixture was cooled with ice
3. additionAfter completion of the dropwise addition
4. waitthe reaction was carried out for 30 minutes
5. temperatureunder cooling with ice
6. extractionextracted with methylene chloride
7. washwashed with water
8. dry with materialThe organic layer was dried over anhydrous sodium sulfate
9. concentrationconcentrated under reduced pressure
10. customThe residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate/n-hexane=1/9)