| 摘要 |
4,4-Dimethyl-1-(p-chlorophenyl)pentan-3-one can be prepared by condensation of pinacolone and p-chlorobenzaldehyde in an alcohol as solvent in the presence of an inorganic base and by subsequent hydrogenation, in which the reaction mixture obtained in the condensation is hydrogenated directly without isolation of the intermediate 4,4-dimethyl-1-(p-chlorophenyl)-1-penten-3-one after the addition of a hydrogenation catalyst at elevated temperature and superatmospheric pressure to give 4,4-dimethyl-1-(p-chlorophenyl)pentan-3-one, after the hydrogenation catalyst has been separated off from the liquid hydrogenation mixture, the alcohol is largely distilled off, and the water content of the bottom product of the distillation is adjusted in such a manner that it separates into an aqueous and an organic phase, and the 4,4-dimethyl-1-(p-chlorophenyl)pentan-3-one is recovered from the organic phase.
|
