反应详情

A stirred mixture of ethyl 3-[(ethoxycarbonyl)amino]-4,4,4-trifluorocrotonate, (Z)-(2.04 g, 8 mmol), isopropylamine (0.567 g, 9.6 mmol), and 1,8-diazabi-cyclo[5,4,0]undec-7-ene (DBU, 1.46 g, 9.6 mmol) in xylene (15 mL) is heated at 100° C. for 3 hours, cooled, and diluted with ethyl acetate. Water is added, and the resultant aqueous mixture is extracted with ethyl acetate. The organic extracts are combined, washed sequentially with water and aqueous 2 N hydrochloric acid, dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to obtain a solid. The solid is crystallized from methanol/water to give the title product as a solid (1.08 g, 61% yield) which is identified by 1H and 19F NMR spectral analyses.

1. temperaturecooled
2. extractionthe resultant aqueous mixture is extracted with ethyl acetate
3. washwashed sequentially with water and aqueous 2 N hydrochloric acid
4. dry with materialdried over anhydrous sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customto obtain a solid
8. customThe solid is crystallized from methanol/water