反应详情

A solution of 0.020 moles of titanium tetrachloride in 5 ml of carbon tetrachloride was added dropwise at room temperature to 50 ml of dichloromethane. The mixture was cooled to 0° and a solution of 0.020 moles of N,N,N',N'-tetramethylethylenediamine in 5 ml of dichloromethane was added dropwise over 15 minutes. After the mixture was stirred an additional hour, a solution of 0.015 moles of ethyl acetoacetate in 10 ml of dichloromethane was added dropwise over 15 minutes. After the mixture was stirred an additional hour, a solution of 0.030 moles of triethylamine in 15 ml of dichloromethane was added over 10 minutes. After thirty minutes, a solution of 0.015 moles of benzaldehyde in 10 ml of dichloromethane was added over 10 minutes. The reaction mixture was stirred for 20 hours. Water (25 ml) was added and the resultant two-phase mixture was stirred for two hours. After the layers were separated, the aqueous layer was extracted with 50 ml of ethyl acetate. The ethyl acetate extract was combined with the initially separated organic layer, dried over sodium sulfate, filtered, and concentrated in vacuo to an oil. Chromatography on silica gel gave the title compound as a solid. The material prepared by this procedure was identical to that prepared by the method of Example 1, as indicated by the reverse phase chromatographic method described in Example 2.

1. temperatureThe mixture was cooled to 0°
2. stirringAfter the mixture was stirred an additional hour
3. waitAfter thirty minutes
4. stirringThe reaction mixture was stirred for 20 hours
5. customAfter the layers were separated
6. extractionthe aqueous layer was extracted with 50 ml of ethyl acetate
7. extractionThe ethyl acetate extract
8. dry with materialdried over sodium sulfate
9. filtrationfiltered
10. concentrationconcentrated in vacuo to an oil