[CH:1]([CH:3]=[CH2:4])=[O:2].[CH:5]([C:8]([CH2:10][CH3:11])=[O:9])([CH3:7])[CH3:6].[C:12]1([CH3:22])[CH:17]=C[C:15](S(O)(=O)=O)=[CH:14][CH:13]=1>O>[CH:1]([CH:3]=[CH2:4])=[O:2].[CH:5]([C:8]([CH2:10][CH3:11])=[O:9])([CH3:7])[CH3:6].[CH3:4][C:3]1[C:1](=[O:2])[C:12]([CH3:22])([CH3:17])[CH2:13][CH2:14][CH:15]=130 g of acrolein (boiling point about 105° C) are added dropwise in the course of 60 minutes to 150 g of ethyl isopropyl ketone and 2 g of p-toluenesulfonic acid, under reflux. The water formed is removed. After 3 hours, the unconverted starting materials are distilled off through a short column under atmospheric pressure at from 40° to 112° C. The reaction mixture ist then kept for 1 hour at an internal temperature of 200° C and is thereafter distilled under reduced pressure. 7 g of water, 3 g of acrolein, 122 g of ethyl isopropyl ketone, 22 g of 2,6,6-trimethyl-cyclohex-2-en-1-one (free from isomers) and 28 g of residue are obtained. This amounts to a yield of 57%, based on ethyl isopropyl ketone employed.
読み込み中…
