反应详情

A 3.9 g. portion of diisopropylamine was dissolved in 200 ml. of dry tetrahydrofuran, and to the solution was added 16 ml. of 2.4-molar butyllithium solution in hexane. The mixture was stirred for 30 minutes and chilled to about -70°. To the mixture was added 10 g. of 1-dimethylamino-2-(3-trifluoromethylphenyl)-1-butene-3-one suspended in 50 ml. of tetrahydrofuran. The temperature rose to about -60°, and the mixture was stirred for 50 minutes and chilled. To the mixture was then added over a period of 1 minute a 4.7 g. portion of pivaloyl chloride. The temperature of the reaction mixture was then about -70°. The mixture was allowed to warm slowly to ambient temperature while it was stirred for 16 hours. The mixture was then diluted with 200 ml. of diethyl ether, and was washed successively with 1 N hydrochloric acid, 1 N sodium hydroxide, and saturated sodium chloride solution. The organic layer was then dried over magnesium sulfate, and was evaporated to dryness under vacuum to obtain 9.1 g. of a dark oil. The oil was chromatographed over a 300 g. silica gel column with 1:10 ethyl acetate:dichloromethane as the eluting solvent. The product-containing portions were combined and evaporated under vacuum to dryness to obtain 1.3 g. of the product, which was identified by nmr analysis, which showed (CDCl3) δ1.03 (s, 9H); 2.78 (s, 6H); 5.03 (s, >1H); 7.53 (broad s, 4H); 7.76 (s, 1H).

1. temperaturechilled to about -70°
2. additionTo the mixture was added 10 g
3. customrose to about -60°
4. stirringthe mixture was stirred for 50 minutes
5. temperaturechilled
6. additionTo the mixture was then added over a period of 1 minute a 4.7 g
7. customabout -70°
8. stirringwas stirred for 16 hours
9. additionThe mixture was then diluted with 200 ml
10. washof diethyl ether, and was washed successively with 1 N hydrochloric acid, 1 N sodium hydroxide, and saturated sodium chloride solution
11. dry with materialThe organic layer was then dried over magnesium sulfate
12. customwas evaporated to dryness under vacuum
13. customto obtain 9.1 g
14. customThe oil was chromatographed over a 300 g
15. customevaporated under vacuum to dryness
16. customto obtain 1.3 g