Mesityl oxide → 4,8-Dimethylnona-3,7-dien-2-one

Reaktionsgleichung

[O:1]=[C:2]([CH:4]=[C:5]([CH3:7])[CH3:6])[CH3:3].[CH3:8][C:9]([CH3:13])=[CH:10][CH2:11]O.CC(C)=CC(O)=O>>[CH3:6][C:5]([CH2:7][CH2:11][CH:10]=[C:9]([CH3:13])[CH3:8])=[CH:4][C:2](=[O:1])[CH3:3]

Komponenten

Edukt 3

HCID 8858Mesityl oxide

HCID 109313-Methyl-2-butenoic acid

HCID 111733-Methyl-2-buten-1-OL

Produkt 1

HCID 5496634,8-Dimethylnona-3,7-dien-2-oneAusbeute 86 %

Versuchsvorschrift

A mixture of 400 parts of mesityl oxide, 100 parts of prenol and 5 parts of 3,3-dimethylacrylic acid is heated for 4 hours at a pressure of 1.9 atmospheres and a temperature of 175°C in a still provided with means for removing water. The water formed is removed azeotropically. The reaction mixture is worked up. 85 parts of 4,8-dimethyl-3,7-nonadien-2-one is obtained. This is equivalent to a yield of 86% of theory at a conversion of 51% based on prenol.